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The application of a habitat suitability index (HSI) assessment to predict the use of ponds by great crested newts (Triturus cristatus) is commonly used in association with distribution and monitoring projects. Such projects are often used to inform development and planning decision making. However, this type of assessment is frequently misused, and misinterpreted. We used a large, commercially collected environmental DNA (eDNA) survey for great crested newt pond occupancy (489 ponds) to; (1) assess whether it is appropriate to use low HSI scores to rule out occupancy, (2) discuss the use of high HSI scores to identify ponds of high importance for the species and, (3) explore the eDNA detection method. We conclude that there is no evidence to support ruling out pond occupancy based on low HSI scores. However, the conventional view that ponds with HSI scores above 0.7 are of high importance to great crested newts is somewhat supported by the data. Both eDNA and direct observational survey methodologies suffer from sampling error and these need to be acknowledged in the analysis of large data sets. [ABSTRACT FROM AUTHOR]

Individual recognition of animal species is a prerequisite for capture-mark-recapture (CMR) studies. For amphibians, photoidentification of body pattern is a non-invasive and less expensive alternative than classical marking methods (e.g. passive integrated transponder). However, photo-identification is effective only if the patterns are (i) sufficiently variable between individuals, and (ii) stable over time. This method also depends on the observer's judgment. In the present study, we assessed the effectiveness of an automatic algorithm (AmphIdent) to recognise ventral colour patterns of the Pyrenean brook newt (Calotrion asper), endemic to the Pyrenees Mountains of France. To assess the performance of the tested method, 113 individuals from two different streams were marked with passive integrated transponders (PIT-tags). We used false rejection rate (FRR), false acceptance rate (FAR) and true acceptance rate (TAR) as metrics to evaluate performances of photoidentification. Mean FRR was 7.3 %, FAR was 5.2 %, and TAR was 92 % across both streams, both sexes and all the observers. FAR was significantly different between sexes, while FRR and TAR were significantly influenced by the interaction between the sex and the stream. Despite these differences, our error rates are among the lowest values found in the literature for both amphibian and non-amphibian computer-assisted photo-identification. We found that poor-quality reference pictures could lead to an increasing difficulty to achieve a correct match when time since first capture rose. Consequently, individual photo-identification using AmphIdent software is a reliable tool to aid in the monitoring the Pyrenean brook newts, provided that pictures are taken with care, reference images are regularly updated and observers are properly trained to use the software and interpret images. [ABSTRACT FROM AUTHOR]

Photo-identification is an increasingly used method for the study of animal populations. Natural marks such as coloration or scale pattern to identify individuals provide an inexpensive and less invasive alternative to conventional tagging methods. Photo-identification has previously been used to distinguish individual snakes, usually by comparing the pileus region. Nevertheless, this method is seldom used in capture-recapture studies. We show the effectiveness of photo-identification in snakes using specific software for individual recognition applied to a wildlife control study of horseshoe whip snakes. Photos were analysed with Automatic Photo Identification Suite (APHIS), which allowed us to compare the variability of head scale patterns surrounding the parietal shields instead of the traditional method of using large scale groups of the pileus. APHIS correctly identified 100% of recaptures of snakes. Although further studies are needed, the variability of the surrounding scales of the pileus region seems a robust method to identify and differentiate individuals. [ABSTRACT FROM AUTHOR]

Using photo-identification techniques, 30 dugongs were recorded at the southern Egyptian Red Sea coast between December 2015 and October 2017, 16 at Marsa Alam and 14 at Wadi El Gemal National Park (WGNP). Males were recorded seven times more frequently than females and calves were also recorded. A Photo ID catalogue was prepared for the dugongs with records of their occurrence among sites. We confirmed the presence of particular dugong specific sites. Long- and short-distance movements within the study sites were recorded for eight different dugongs. This is the first study to document the number of dugongs in inshore areas of the Egyptian Red Sea coast. Further studies are recommended for offshore sites in WGNP for better documentation of this group of animals. [ABSTRACT FROM AUTHOR]

The article offers information on Bryde's whales also known as Balaenoptera edeni with details on their foraging region which lies near the Weizhou Island of China in the Beibu Gulf. Topics discussed include occurrence of Bryde's whale strandings along the coasts of China, conduction of vessel-based photo-identification surveys of the whales and details on their sightings.

Understanding the drivers underlying fluctuations in the size of animal populations is central to ecology, conservation biology, and wildlife management. Reliable estimates of survival probabilities are key to population viability assessments, and patterns of variation in survival can help inferring the causal factors behind detected changes in population size. We investigated whether variation in age‐ and sex‐specific survival probabilities could help explain the increasing trend in population size detected in a small, discrete population of bottlenose dolphins Tursiops truncatus off the east coast of Scotland. To estimate annual survival probabilities, we applied capture–recapture models to photoidentification data collected from 1989 to 2015. We used robust design models accounting for temporary emigration to estimate juvenile and adult survival, multistate models to estimate sex‐specific survival, and age models to estimate calf survival. We found strong support for an increase in juvenile/adult annual survival from 93.1% to 96.0% over the study period, most likely caused by a change in juvenile survival. Examination of sex‐specific variation showed weaker support for this trend being a result of increasing female survival, which was overall higher than for males and animals of unknown sex. Calf survival was lower in the first than second year; a bias in estimating third‐year survival will likely exist in similar studies. There was some support first‐born calf survival being lower than for calves born subsequently. Coastal marine mammal populations are subject to the impacts of environmental change, increasing anthropogenic disturbance and the effects of management measures. Survival estimates are essential to improve our understanding of population dynamics and help predict how future pressures may impact populations, but obtaining robust information on the life history of long‐lived species is challenging. Our study illustrates how knowledge of survival can be increased by applying a robust analytical framework to photoidentification data. We applied capture–recapture models to photoidentification data to investigate whether variation in age‐ and sex‐specific survival probabilities could help explain a detected increasing trend in abundance in a small, discrete bottlenose dolphin population. We found strong support for an increase in juvenile/adult annual survival from 93.1% to 96.0% from 1989 to 2015, most likely caused by a change in juvenile survival. There was weaker support for this trend being a result of increasing female survival, which was overall higher than for males and animals of unknown sex. Calf survival was lower in the first than second year. [ABSTRACT FROM AUTHOR]

The estimation of demographic parameters in wild populations is strengthened by individual identification. For amphibians, various techniques are used to either temporarily or permanently mark individuals for identification. Photo-identification of body patterns offers a non-invasive technique. However, the reliability of photo-recognition software is key to the reliable estimation of the true demographic parameters. In the current study, we assessed the effectiveness of fully-automated and semi-automated software: Wild-ID and APHIS. We used the cryptic salamander Hydromantes strinatii as our study species. We used the False Rejection Rate (FRR) of Top 1, Top 5 and Top 10 matches of chest and cloaca pictures. Finally, we assessed the bias induced by our FRR for the estimation of population size through simulation. Wild-ID FRRs ranged from 0.042 to 0.093 while APHIS' ranged from 0.227 to 0.547. Wild-ID was equally efficient with pictures from the chest and from the cloaca, while APHIS was significantly more efficient with chest pictures than cloaca pictures. Cropping pictures did not significantly improve Wild-ID effectiveness. Our Wild-ID FRRs are among the lowest ever obtained from pictures of an amphibian with a complex chromatophore pattern. Simulation showed that the Top 10 FRR from selected software Wild-ID induced a low bias 2.7% on the estimation of population size. The effectiveness and plasticity of Wild-ID provides opportunities for reliably monitoring amphibian species with complex colour patterns. [ABSTRACT FROM AUTHOR]

The challenges of monitoring fully aquatic and long-living mammals have limited research on cetaceans that spans several decades to only a few populations. We report the first long-term assessment of association and residency patterns of dusky dolphins (Lagenorhynchus obscurus) off Kaikoura, New Zealand. Dorsal fin images, spanning 30 years of data collection, were used for photo-identification and social structure analyses. A total of 4,022 uniquely marked individuals were identified. Most (80%) were sighted only one time. The population of dusky dolphins off Kaikoura appears to be open, with the possibility of immigration and emigration. Dusky dolphins showed preferences for assembly into either large or small groups, which appear to drive association patterns. They did not demonstrate significant preferred or avoided associations with each other, and had overall weak association patterns. Individuals reside in the Kaikoura area for approximately eight years, and also have temporallv stable associations lasting approximately eight years. Dusky dolphins fit the model of a fission-fusion societv, and their association patterns may reflect unique local ecological conditions and foraging opportunities. [ABSTRACT FROM AUTHOR]

Over four decades ago, a short paper demonstrated how photographs of free-swimming dolphins could be used to reveal scientific information about cetaceans. That paper, and a few others published during the same time period, illustrated a research technique that has become foundational in the field of marine mammalogy and resulted in a cascade of science. Photographs can be used to identify individuals, providing insights into movements, migrations, site fidelity, school structure and stability, and abundance. Photographs can be used to estimate group size and improve the precision of abundance estimates. Photographs can characterize reproductive output at the population level. Photographs allow for quantification of morphology, yielding insights into classification at a variety of taxonomic levels; and they provide a means to assess the condition and health of individual animals. And photographs can provide insights into behavior. The information photographs convey and their applications to cetacean research are ever-increasing. Ultimately, photographs have provided a high-quality and relatively inexpensive means to increase the knowledge base for most cetacean species in all of the oceans of the world through research conducted by scientists nations, and through of developed and developing citizen science conducted by non-scientists. [ABSTRACT FROM AUTHOR]

Home range sizes have been determined for few odontocete populations, although the understanding of comparative trends in range utilization is important for conservation. Most of the published knowledge of the Hector's dolphins (Cephalorhynchus hectori) of New Zealand, originates from one well-studied population around Banks Peninsula. Its ranging behavior has been described previously by a decades-long photo-identification (ID) study and by a shorter radio-telemetry study. Little is known, however, about how the dolphins utilize their home range in other coastal areas around the South Island of New Zealand. We used an intensive three-year photo-ID study to define the movement patterns of Hector's dolphins over diel and seasonal scales. Significant differences in the average movement behavior between the East Coast populations off Kaikoura and Moeraki and the West Coast populations off Westport-Greymouth and in Jackson Bay are identified. Movement patterns optimizing range utilization in relation to prey abundance and accessibility are discussed. At the Kaikoura study area, the mean distances between consecutive sightings and speeds of dolphins were considerably reduced compared to other coastal areas. Therefore, the photo-ID study was extended off Kaikoura to cover a total of 14 years. Those findings can be explained by the existence of an environmental barrier (i.e., the deep-water Kaikoura Canyon) that almost completely interrupts Hectors dolphin movements over die short distance of 15 km and very likely has led to a reduced genetic exchange. In conjunction with two recent studies, we present evidence of the impact of an environmental barrier on the population structure and foraging behavior of this shallow-water dolphin. [ABSTRACT FROM AUTHOR]

The article presents the results of a study which analyzed bite marks and scars on western gray whales (Eschrichtius robustus) by killer whales (Orcinus orca). Topics of discussion include photoidentification of gray whales off Sakhalin Island, Russia, in the North Pacific Ocean, new scars by non-calf whales, and sex ratio among gray whales.

The southern distribution limit of the Iberian endemic and threatened golden-striped salamander (Chioglossa lusitanica) is located about 170 km NE of Lisbon, Portugal. In 1943 Anthero Seabra reportedly introduced a few specimens in the Sintra mountains, about 20 km NW of Lisbon, but the exact introduction site is not known. The existence of a reproducing population in Sintra became a recurrent topic among herpetologists and, despite the efforts of several individuals and teams, was not confirmed until now. After a fortuitous finding of one individual, we report here the results of a monitoring program involving photoidentification of adults and juveniles conducted during the autumn and winter of 2015/16 and 2016/17. We found a reproducing population living along a 107 m stretch of a single stream. Phenology and larval sizes were similar to those of other populations. Notable aspects of this population are its small size (estimated at 339 ± 35 individuals) and confinement to a very small area, the low proportion of individuals that were recorded moving along the stream and the very short distances travelled by those individuals, and the large size of several adults, including the longest individual recorded so far. [ABSTRACT FROM AUTHOR]

Abstract: Little is known about harbor porpoises at the individual level or local group structure. Group characteristics, site fidelity, and photo‐identification of harbor porpoises were investigated off Fidalgo Island, Washington State. Harbor porpoise presence was affected by season and rip tide strength (Wald χ2P < 0.04); calf presence was influenced by season and tide (Wald χ2P < 0.0075). Average group size (2.32 ± 1.38, n = 266) was influenced by season, behavior, and calf presence (F7 = 9.71, P < 0.0001, R2 = 0.294). Fifty‐three individuals were identified using a matrix of primary, secondary, and confirmation markings that were stable over months/years. Over 35% were resighted in more than 1 mo (range 1–7, x ¯ = 1.83); 15.1% were seen in more than 1 yr, suggesting some level of residency. Despite having higher effort, presence and group size were significantly lower in Summer. Variations in the significance of rip tide strength and tides relate to calf presence and support other findings that harbor porpoise population structure is complex and varies at small spatiotemporal scales and may also vary between populations and habitats. This study identifies variables affecting group characteristics and emphasizes the importance of research on local populations of harbor porpoises. [ABSTRACT FROM AUTHOR]

Historically, Fin Whales (Balaenoptera physnlus) were relatively common off the west coast of North America but very few records of their occurrence in waters between Vancouver Island and continental North America exist. To confirm their presence in these waters we collected photographs documenting at least 13 unique individuals during 43 encounters from 1999 to 2017. These records are the first of live Fin Whales in Queen Charlotte, Johnstone, Georgia and Juan De Fuca Straits and are also the only confirmed sightings between Vancouver Island and continental North America since 1930. Additionally, 12 dead Fin Whales all with evidence of ship strikes are reported in these waters between 1986 and 2017. Most (88%) sightings of live Fin Whales occurred between July and October and no individuals were documented dead or alive between January and April. We suggest that Fin Whales in coastal waterways may be at greater risk to ship strikes and predation by mammal-eating Killer Whales (.Orcimis oral) than in less confined waters further offshore. [ABSTRACT FROM AUTHOR]

Bottlenose dolphins along the northern Gulf of Mexico continue to be impacted by numerous stressors including harmful algal blooms, infectious disease epizootics, and oil exposure following the Deepwater Horizon (DWH) oil spill. Studies to assess the potential impacts of the DWH oil spill on dolphins in the northern Gulf of Mexico were initiated as part of a Natural Resource Damage Assessment and included photographic-identification (photo ID) surveys to determine abundance, density, and site fidelity in St. Joseph Bay, Florida (SJB). Although significant oiling did not occur in SJB, long-term data have been collected in this region to provide insight into population-level trends in abundance/density over time. Thus, SJB dolphins could serve as a reference for comparison to other dolphin populations exposed to DWH oiling. During 2005-2007, the results of photo ID and telemetry surveys determined seasonal fluctuations in abundance and identified two different dolphin populations in SJB: residents sighted across multiple seasons and years (St. Joseph Bay Stock), and visitors that were present during the spring and fall and associated with a 2-3fold increase in abundance (Northern Coastal Stock). The goals for the current study were to compare dolphin abundance, density, and site fidelity, prior to (2005-2007), during (2010), and post-DWH (2011 and 2013) using photo-ID surveys and a spatially explicit robust-design capture-recapture (SERDCR) model. The data collected during and post-DWH paralleled previous research in that a low number of individuals with high site fidelity were sighted across seasons and years (St. Joseph Bay Stock), and abundance/density increased in the fall as a result of an influx of dolphins that were likely members of the Northern Coastal Stock. However, June and August 2010 abundance (347; 193-498, 95% CI and 394; 288-534, 95% CI, respectively), density (dolphins/km2) (2.60; 1.36-3.70, 95% CI and 2.55; 1.89-3.29, 95% CI, respectively), and site fidelity patterns were more similar to previous years' spring and fall data, with high abundance estimates, increased dolphin density in coastal waters, and elevated numbers of individuals with low site fidelity in the SJB region. Factors that could have contributed to this increase in abundance include immigration of dolphins from adjacent estuaries, population growth within the St. Joseph Bay Stock, impacts from DWH oiling, and environmental and/or prey-based cues that influence movements of the Northern Coastal Stock. The results of this study demonstrate the importance of long-term monitoring to assess impacts of current and future stressors on the dolphins in the northern Gulf of Mexico. [ABSTRACT FROM AUTHOR]

Humpback whales migrate seasonally from high latitude feeding areas to lower latitude breeding areas for mating and calving. In 2004-2006, a North Pacific basin-wide study called SPLASH was conducted as an international collaboration among various groups of researchers. The Russian Far East consists of multiple high latitude feeding areas and during SPLASH, 102 whales were identified and compared to catalogs from breeding areas. Our goal in this study was to further investigate the migratory destinations of whales from the Russian Far East using a total of 1,459 photographs of whales identified from 2004 to 2014. We compared the latest Russian catalog with the SPLASH catalog from wintering areas (2004-2006) and with two additional regional catalogs from Okinawa (1989-2006) and the northern Philippines (2000-2006). We found a total of 152 matches: 106 with Asian, 35 with Hawaiian, and 11 with Mexican breeding grounds. The match rate was higher in mainland Kamchatka and consisted mostly of whales from the Asian breeding ground. In the Commander Islands, the proportion of whales from Asia was twice that of Hawaii and six times higher than Mexico. The total match rate was low, supporting the hypothesis of some undiscovered humpback whale breeding location in the North Pacific. [ABSTRACT FROM AUTHOR]

Long-term studies often rely on natural markings for individual identification across time. The primary method for identification in small cetaceans relies on dorsal fin shape, scars, and other natural markings. However, dorsal fin markings can vary substantially over time and the dorsal fin can become unrecognizable after an encounter with a boat or shark. Although dorsal fins have the advantage in that they always break the water surface when the cetacean breathes, other physical features, such as body scars and pigmentation patterns can supplement. The goal of this study was to explore the use of dorso-lateral pigment patterns to identify wild bottlenose dolphins. We employed photographic pigment matching tests to determine if pigmentation patterns showed (1) longitudinal consistency and (2) bilateral symmetry using a 30 yr photographic database of bottlenose dolphins ( Tursiops aduncus). We compared experienced dolphin researchers and inexperienced undergraduate student subjects in their ability to accurately match images. Both experienced and inexperienced subjects correctly matched dolphin individuals at a rate significantly above chance, even though they only had 10 s to make the match. These results demonstrate that pigment patterns can be used to reliably identify individual wild bottlenose dolphins, and likely other small cetacean species at other sites. [ABSTRACT FROM AUTHOR]

Background: Ecological research often requires monitoring of a specific individual over an extended period of time. To enable non-invasive re-identification, consistent external marking is required. Treefrogs possess lateral lines for crypticity. While these patterns decrease predator detection, they also are individual specific patterns. In this study, we tested the use of lateral lines in captive and wild populations of Dryophytes japonicus as natural markers for individual identification. For the purpose of the study, the results of visual and software assisted identifications were compared. Results: In normalized laboratory conditions, a visual individual identification method resulted in a 0.00 rate of false-negative identification (RFNI) and a 0.0068 rate of false-positive identification (RFPI), whereas Wild-ID resulted in RFNI = 0.25 and RFNI = 0.00. In the wild, female and male data sets were tested. For both data sets, visual identification resulted in RFNI and RFPI of 0.00, whereas the RFNI was 1.0 and RFPI was 0.00 with Wild-ID. Wild-ID did not perform as well as visual identification methods and had low scores for matching photographs. The matching scores were significantly correlated with the continuity of the type of camera used in the field. Conclusions: We provide clear methodological guidelines for photographic identification of D. japonicus using their lateral lines. We also recommend the use of Wild-ID as a supplemental tool rather the principal identification method when analyzing large datasets. [ABSTRACT FROM AUTHOR]

Latitudinal preferences within the breeding range have been suggested for Breeding Stock G humpback whales that summer in different feeding areas of the eastern South Pacific. To address this hypothesis, humpback whales photo-identified from the Antarctic Peninsula and the Fueguian Archipelago (southern Chile) were compared with whales photo-identified from lower latitudes extending from northern Peru to Costa Rica. This comparison was performed over a time span that includes 18 austral seasons. A total of 238 whales identified from the Antarctic Peninsula and 25 whales from the Fueguian Archipelago were among those photo-identified at the breeding grounds. Our findings showed that humpback whales from each feeding area were resighted unevenly across the breeding grounds, which suggests a degree of spatial structuring in the migratory pathway. Humpback whales that feed at the Antarctic Peninsula were more likely to migrate to the southern breeding range between northern Peru and Colombia, whereas whales that feed at the Fueguian Archipelago were more likely to be found in the northern range of the breeding ground off Panama. Further photo-identification efforts and genetic sampling from poorly sampled or unsampled areas are recommended to confirm these reported connectivity patterns. [ABSTRACT FROM AUTHOR]

Photo-identification is an invaluable method for documenting associations. Based on the assumption that individuals photographed close together in time are physically close in space, the metadata associated with digital photography offers an opportunity to base association analyses on time between images. This was tested via analysis of associations within a population of bottlenose dolphins (Tursiops truncatus) in Doubtful Sound, New Zealand. We compared the widely used group-membership method and an alternative time-based method. Overall social structures between methods were similar; high degrees of association among all individuals and little support for sub-groups. Results also indicated an increase in the precision of pairwise indices for the time-based method. This study validated the approach of using time as a basis for analyses of associations. Importantly, this method can be retrospectively applied to any photo-ID data set in which images of uniquely identifiable individuals are time-stamped by the camera. [ABSTRACT FROM AUTHOR]

The predictable occurrence of whale sharks, Rhincodon typus, has been well documented in several areas. However, information relating to their migratory patterns, residency times and connectivity across broad spatial scales is limited. In the present study photo-identification data is used to describe whale shark population structure and connectivity among known aggregation sites within the Western Central Atlantic Ocean (WCA). From 1999 to 2015, 1,361 individuals were identified from four distinct areas: the Yucatan Peninsula, Mexico (n = 1,115); Honduras (n = 146); northern Gulf of Mexico, United States (n = 112), and Belize (n = 49). Seasonal patterns in whale shark occurrence were evident with encounters occurring in the western Caribbean Sea earlier in the year than in the GOM. There was also a significant sex bias with 2.6 times more males present than females. Seventy sharks were observed in more than one area and the highest degree of connectivity occurred among three aggregation sites along the Mesoamerican Reef. Despite this, the majority of resightings occurred in the area where the respective sharks were first identified. This was true for the WCA as a whole, with the exception of Belize. Site fidelity was highest in Mexico. Maximum likelihood modelling resulted in a population estimate of 2,167 (95% c.i. 1585.21–2909.86) sharks throughout the entire region. This study is the first attempt to provide a broad, regional population estimate using photo-identification data from multiple whale shark aggregations. Our aim is to provide population metrics, along with the description of region-scale connectivity, that will help guide conservation action in the WCA. At a global level, rapidly growing photographic databases are allowing for researchers to look beyond the description of single aggregation sites and into the ocean-scale ecology of this pelagic species. [ABSTRACT FROM AUTHOR]

Photographic capture-recapture is a valuable tool for obtaining demographic information on wildlife populations due to its noninvasive nature and cost-effectiveness. Recently, several computer-aided photo-matching algorithms have been developed to more efficiently match images of unique individuals in databases with thousands of images. However, the identification accuracy of these algorithms can severely bias estimates of vital rates and population size. Therefore, it is important to understand the performance and limitations of state-of-the-art photo-matching algorithms prior to implementation in capture-recapture studies involving possibly thousands of images. Here, we compared the performance of four photo-matching algorithms; Wild- ID, I3S Pattern+, APHIS, and AmphIdent using multiple amphibian databases of varying image quality. We measured the performance of each algorithm and evaluated the performance in relation to database size and the number of matching images in the database. We found that algorithm performance differed greatly by algorithm and image database, with recognition rates ranging from 100% to 22.6% when limiting the review to the 10 highest ranking images. We found that recognition rate degraded marginally with increased database size and could be improved considerably with a higher number of matching images in the database. In our study, the pixel-based algorithm of AmphIdent exhibited superior recognition rates compared to the other approaches. We recommend carefully evaluating algorithm performance prior to using it to match a complete database. By choosing a suitable matching algorithm, databases of sizes that are unfeasible to match 'by eye' can be easily translated to accurate individual capture histories necessary for robust demographic estimates. [ABSTRACT FROM AUTHOR]

Lesions on cetacea can be useful to assess the natural and anthropogenic pressures faced by a population. The aim of this study was to assess the viability of photo-identification (photo-ID) as a tool to examine potential pressures affecting gregarious, free-ranging common dolphins (Delphinus sp.). Photo-ID was collected between 2010 and 2013 in the Hauraki Gulf (HG), New Zealand. From 1,411 independent encounters, 2,083 individuals were identified from permanent nicks and notches on their dorsal fins. Of these individuals, the number of lesions on 12 body sectors was assessed. Prevalence was determined by weighting the number of lesions by the cumulative number of images for each body sector. Of the 2,083 individuals identified, 77.9% (n = 1,622) exhibited lesions. Of all body segments examined, the anterior peduncle exhibited the highest percentage of lesions (91.1%). Most lesions observed were represented by indentations and impressions (84.2%, n = 1,368), followed by cut-like indentations (54.1%, n = 878), hyper-pigmented lesions (43.1%, n = 700), and hypo-pigmented lesions (37.4%, n = 607). A significant difference in the prevalence of lesions between the leading and trailing edges of dorsal fins was evident. Possible causes of lesions are discussed, including intra- or interspecific interactions, environmental conditions, infectious origins, fisheries and vessel interactions, and/or human-induced environmental stressors. Findings suggest that despite limitations, photo-ID can be used as an opportunistic, non-invasive research tool to examine lesions on free-ranging delphinids. [ABSTRACT FROM AUTHOR]

Photo-identification studies of humpback whales off eastern Australia show low levels of movement between eastern Australia and New Caledonia whales. Some eastern Australian humpback whales migrate through the southern waters of New Zealand on route to Antarctic feeding areas. Photoidentification studies have shown that the waters near the Balleny Islands, in Antarctic Area V, are a feeding area for some eastern Australian humpback whales. However, such studies provide no details of the routes taken between New Zealand and Australia and to and from Antarctic feeding areas. Sixteen humpback whales were satellite-linked radio tagged off Eden NSW in 2008. The number and duration of the tag positions reported revealed complete migratory transits from Eden to Antarctic Area V and IV feeding areas. Photographs of the Eden humpback whales were compared to the Hervey Bay photo-identification catalogue and yielded two matches, identified from lateral body marks and dorsal fins. This study provides the first evidence that during the southern migration some humpback whales stopover at Hervey Bay and also migrate past Eden on the NSW coast. The tracks of the two whales from Eden showed that a male sighted in Hervey Bay in the same season moved southeast from Eden towards southern New Zealand. A female with site-fidelity to Hervey Bay in previous seasons, accompanied by a calf when the tag was deployed, moved down and around the coast of Victoria, across Bass Strait and then southwest into the Antarctic Area IV feeding area. Eden may be a migratory hub for humpback whales departing from and approaching the east coast of Australia. This study suggests that eastern Australian humpback whales may exhibit a more diverse range of feeding destinations, after leaving Australian coastal waters, than previously reported. [ABSTRACT FROM AUTHOR]

Unmanned aerial systems (UAS), commonly referred to as drones, are finding applications in several ecological research areas since remotely piloted aircraft (RPA) technology has ceased to be a military prerogative. Fixed-wing RPA have been tested for line transect aerial surveys of geographically dispersed marine mammal species. Despite many advantages, their systematic use is far from a reality. Low altitude, long endurance systems are still highly priced. Regulatory bodies also impose limitations while struggling to cope with UAS rapid technological evolution. In contrast, small vertical take-off and landing (VTOL) UAS have become increasingly affordable but lack the flight endurance required for long-range aerial surveys. Although this issue and civil aviation regulations prevent the use of VTOL UAS for marine mammal abundance estimation on a large scale, recent studies have highlighted other potential applications. The present note represents a general overview on the use of UAS as a survey tool for marine mammal studies. The literature pertaining to UAS marine mammal research applications is considered with special concern for advantages and limitations of the survey design. The use of lightweight VTOL UAS to collect marine mammal behavioral data is also discussed. [ABSTRACT FROM AUTHOR]

Camera trapping is a standard tool in ecological research and wildlife conservation. Study designs, particularly for small-bodied or cryptic wildlife species often attempt to boost low detection probabilities by using non-random camera placement or baited cameras, which may bias data, or incorrectly estimate detection and occupancy. We investigated the ability of non-baited, multi-camera arrays to increase detection probabilities of wildlife. Study design components were evaluated for their influence on wildlife detectability by iteratively parsing an empirical dataset (1) by different sizes of camera arrays deployed (1–10 cameras), and (2) by total season length (1–365 days). Four species from our dataset that represented a range of body sizes and differing degrees of presumed detectability based on life history traits were investigated: white-tailed deer (Odocoileus virginianus), bobcat (Lynx rufus), raccoon (Procyon lotor), and Virginia opossum (Didelphis virginiana). For all species, increasing from a single camera to a multi-camera array significantly improved detection probability across the range of season lengths and number of study sites evaluated. The use of a two camera array increased survey detection an average of 80% (range 40–128%) from the detection probability of a single camera across the four species. Species that were detected infrequently benefited most from a multiple-camera array, where the addition of up to eight cameras produced significant increases in detectability. However, for species detected at high frequencies, single cameras produced a season-long (i.e, the length of time over which cameras are deployed and actively monitored) detectability greater than 0.75. These results highlight the need for researchers to be critical about camera trap study designs based on their intended target species, as detectability for each focal species responded differently to array size and season length. We suggest that researchers a priori identify target species for which inference will be made, and then design camera trapping studies around the most difficult to detect of those species. [ABSTRACT FROM AUTHOR]

The article presents the study on interaction between bottlenose dolphin and sharks through shark bite wounds and scars on dolphins in the photographic identification surveys. Topics discussed include impacts on resident community of dolphins, estimation of behavioral changes along with the survival rate of dolphins due to changes in shark predator distributions or abundance; and frequency of shark bites more than scarring frequencies which causes due to anthropogenic sources.

The spotted eagle ray Aetobatus narinari is characterized by pigmentation patterns that are retained for up to 3·5 years. These pigmentations can be used to identify individuals through photo-identification. Only one study has validated this technique, but no study has estimated the percentage of correct identification of the rays using this technique. In order to carry out demographic research, a reliable photographic identification technique is needed. To achieve this validation for A. narinari, a double-mark system was established over 11 months and photographs of the dorsal surface of 191 rays were taken. Three body parts with distinctive natural patterns were analysed (dorsal surface of the cephalic region, dorsal surface of the pectoral fins and dorsal surface of the pelvic fins) in order to determine the body part that could be used to give the highest percentage of correct identification. The dorsal surface of the pectoral fins of A. narinari provides the most accurate photo-identification to distinguish individuals (88·2%). [ABSTRACT FROM AUTHOR]

We describe feeding-site fidelity in terms of the rate of annual return by individual humpback whales ( Megaptera novaeangliae (Borowski, 1781)) to Kodiak Archipelago and Shumagin Islands feeding areas and the rate of exchange between these Gulf of Alaska feeding aggregations. Individual whales were photo-identified in both regions between 1999 and 2015 during vessel surveys, either throughout the feeding season (Kodiak region) or in brief 7- to 10-day windows (Shumagin Islands). Feeding-site fidelity was assessed in terms of individuals' annual return rate, sighting interval, total number of years sighted, and movement between feeding areas. We found similarly high degrees of site fidelity in both regions and limited movement of individuals between them, suggesting that the Shumagin Islands and Kodiak Archipelago represent distinct feeding aggregations. Results did not appear affected by temporal differences in sampling strategy in these study areas. [ABSTRACT FROM AUTHOR]

Surveying endangered species is necessary to evaluate conservation effectiveness. Camera trapping and biometric computer vision are recent technological advances. They have impacted on the methods applicable to field surveys and these methods have gained significant momentum over the last decade. Yet, most researchers inspect footage manually and few studies have used automated semantic processing of video trap data from the field. The particular aim of this study is to evaluate methods that incorporate automated face detection technology as an aid to estimate site use of two chimpanzee communities based on camera trapping. As a comparative baseline we employ traditional manual inspection of footage. Our analysis focuses specifically on the basic parameter of occurrence where we assess the performance and practical value of chimpanzee face detection software. We found that the semi-automated data processing required only 2-4% of the time compared to the purely manual analysis. This is a non-negligible increase in efficiency that is critical when assessing the feasibility of camera trap occupancy surveys. Our evaluations suggest that our methodology estimates the proportion of sites used relatively reliably. Chimpanzees are mostly detected when they are present and when videos are filmed in high-resolution: the highest recall rate was 77%, for a false alarm rate of 2.8% for videos containing only chimpanzee frontal face views. Certainly, our study is only a first step for transferring face detection software from the lab into field application. Our results are promising and indicate that the current limitation of detecting chimpanzees in camera trap footage due to lack of suitable face views can be easily overcome on the level of field data collection, that is, by the combined placement of multiple high-resolution cameras facing reverse directions. This will enable to routinely conduct chimpanzee occupancy surveys based on camera trapping and semi-automated processing of footage. RESEARCH HIGHLIGHTS Using semi-automated ape face detection technology for processing camera trap footage requires only 2-4% of the time compared to manual analysis and allows to estimate site use by chimpanzees relatively reliably. [ABSTRACT FROM AUTHOR]

We present an automatic program of blue whale photo-identification for mobile devices. The proposed technique works in the wavelet domain to reduce the image size and the processing time of the proposed algorithm, and with an edge enhancement filter, the characteristics of the blue whale are preserved. Additionally, an image palette reduction algorithm based on local image complexity estimation is introduced to eliminate redundant colors, thus decreasing the number of pixels that are bad classified in the segmentation process and minimizing the resource consumption of the mobile device. The segmented image is obtained with the FCM (fuzzy C-means) or K-means algorithms incorporating a dynamic filtering which is proposed in this paper to improve the brightness and contrast of the acquired image increasing the performance of the image segmentation. Experimental results show that the proposed approach potentially could provide a real-time solution to photo-id of blue whale images and it can be transportable and portable power for mobile devices. Finally, the proposed methodology is simple, efficient, and feasible for photo-id applications in mobile devices. [ABSTRACT FROM AUTHOR]

Assessing the conservation status of protected species needs quantitative population data, generally obtained using Capture-Mark-Recapture methods ( CMR). The exploitation of natural marking (e.g. individual morphological traits) offers an interesting alternative, based on image analyses, which may result in a less manipulation of protected species compared to the typical artificial marking method., In our 2-year CMR study, we tested for the first time in the natural setting the feasibility and the application of the computer-aided photographic identification method of Rosalia alpina using the individual elytral spots as the natural marking. The I3 SC software was used for the photographic analysis., Data were collected from populations of two National Parks of central Italy during July-August in 2014 and 2015. We developed a standard procedure in order to optimise the image acquisition in the field and to acquire clear and comparable images, facilitating the I3 SC screening process., The results demonstrated that the computer-aided photographic identification of natural markings can be implemented in a CMR population study of R. alpina. Our image processing approach showed that using only the elytral central spot contours made the tracing contour process less time-consuming obtaining reliable results. Furthermore, I3 SC output scores were used to identify a threshold value for the identification of new individuals or recaptures, facilitating the final identification proposed by operators., Finally, we assessed the possibility of performing the methodology using a Citizen Science approach. [ABSTRACT FROM AUTHOR]

The franciscana (Pontoporia blainvillei) is a small cetacean endemic to the South Atlantic distributed in coastal waters from Espírito Santo State in Brazil to Chubut Province in Argentina. Babitonga Bay, on the northern coast of Santa Catarina State, Brazil, is home to the only known franciscana population that resides throughout the year in an estuary. Photo-identification is a technique that serves to identify individuals in their natural environment through photographs of natural or artificial body marks. The objective of this paper was to assess the feasibility of identifying individuals from this population from marks present on the dorsal fin and the body. From February 2011 to August 2013, 172 boat surveys were carried out in Babitonga Bay. Groups of franciscanas were recorded on 576 occasions and on 542 of these (94.09%) were photographed. A total of 6,953 (11.89%) from a total of 58,471 photographs were considered of high enough quality to distinguish the features used to identify individuals. Throughout the sampling period, 23 franciscanas were identified. Most of the animals exhibited nicks on the trailing edge of the dorsal fin (82.6%), a mark of longterm duration. Scratches were recorded on only one animal on a single occasion. The rate of resightings ranged from 5.26% to 78.95%, with 39.13% of the individuals showing a rate higher than 50%. A total of 41.8% of the Babitonga Bay population was identified by the presence of marks on the dorsal fin. The study indicates that photo-identification can be applied to franciscanas, which may allow the realisation of various future studies. Because of this species threatened status, the use of this technique may become particularly important for monitoring franciscanas in Babitonga Bay and perhaps in other regions. [ABSTRACT FROM AUTHOR]

Individual marking allows researchers to collect important data using Mark-recapture method. Photographic Identification Method (PIM) has obtained favorable opinions, being effective and less intrusive with respect to traditional marking procedures. Here, we developed and tested the efficacy of a software-aided PIM based on different characteristics, which act as natural marks. Target species were the northern spectacled salamander ( Salamandrina perspicillata, Amphibia: Urodela) and the stag beetle ( Lucanus cervus , Coleoptera: Lucanidae). We considered as natural mark the ventral pattern of S. perspicillata and, for the first time in L. cervus , the presence/number of small denticles on male mandibles. We selected 4 independent characteristics, each one with several states, for each species. We asked participants, with different degree of familiarity with the species, to identify recaptured individuals through manual PIM. To assess the advantages of the software, we compared the time spent by experts of the species to identify an individual through manual PIM and software-aided PIM. We further compared our semi-automated method with a fully automated one. The software efficiency was calculated by increasing the number of characteristics used to filter individuals from the database (from 1 to 4). The chosen characteristics proved their reliability for individual identification and can be used as natural marks. The proposed software-aided PIM shorten the identification time, does not led to mismatching errors and proved its efficacy regardless of the taxa/characteristic used. Thus, this tool can be consider a more practical alternative to conventional marking techniques, in particular for sensitive and threatened species that need quick and effective monitoring programs carried out with non-invasive sampling methods. [ABSTRACT FROM AUTHOR]

Estimating population size is crucial for managing populations of threatened species. In the Top End of northern Australia, populations of northern quolls (Dasyurus hallucatus), already affected by livestock grazing, inappropriate burning regimes and predation, have collapsed following the spread of the toxic cane toad (Rhinella marina). Cane toads are currently invading the Kimberley, where they pose a threat to quoll populations. To manage these populations, we need reliable methods for detecting and estimating quoll abundance. We deployed camera traps with lures containing tuna, peanut butter or no bait and found that baited cameras performed better than the unbaited control. Cameras with a tuna lure detected more individuals than cameras baited with peanut butter or no bait. Cameras with a tuna lure yielded more photographs per quoll than those baited with peanut butter or no bait. We identified individual quolls from unique spot patterns and found multiple photographs improved the accuracy of identification. We also found that population estimates for the sample area derived from camera trapping were consistent with those from live trapping using mark-recapture techniques. [ABSTRACT FROM AUTHOR]

Individual identification is a beneficial tool in behavioural and ecological research. In mark-recapture studies, for example, it can improve abundance, residency and site fidelity estimates. Two non-invasive, photo-identification approaches, using whisker spot patterns, were tested to identify wild individual Australian sea lions (Neophoca cinerea). The Chamfer distance transform algorithm has shown promising results when applied to captive individuals. An alternative matching method using row/column locations of whisker spots, previously applied to lions (Panthera leo) was also tested. Resighting wild N. cinerea in this study proved unfeasible with both methods. Excessive variation between photographs of the same individual was found when applying the Chamfer distance transform, and similarity between photograph-pairs appeared to decrease with increasing time between photographs. Insufficient variation among N. cinerea row/column pattern was detected to successfully discriminate among individuals, averaging 39 mystacial spots (range 30-46, n = 20) in seven rows and 9-10 columns. Additionally, different observers marking the same photographs introduced considerable variation. Colour difference (red, green and blue colour levels) between the whisker spots and surrounding fur affected marking spot locations significantly, increasing uncertainty when contrast decreased. While other pattern-matching algorithms may improve performance, accurate identification of spot locations was the current limitation. [ABSTRACT FROM AUTHOR]

The article focuses on the distribution, ecology, or abundance estimates of Indo-Pacific humpback dolphins or Sousa chinensis in Kuching Bay, East Malaysia. Topics include the photo-identification of humpback dolphins, calculation of the population size by combining the left or right sides of dorsal fins (LDFs and RDFs), and photo-identification during dolphin sighting.

During October and November 2015, the first systematic survey ofSousa teusziiwas carried out in the Saloum Delta (Senegal, West Africa), comprising 1 617.5 km of boat-based survey coverage. Thirty sightings were recorded in the Saloum and Diomboss rivers, and along the southern coastline. Dolphins were also observed entering the Bandiala and Djinack channels, and travelling across the border into Gambia. The initial sighting locations were 0.043–1.192 km from shore, and tracked dolphins did not move more than 2.082 km from shore. Groups comprised 1–29 animals (mean 9.3 animals), and at least three neonate calves were observed during November. The overall relative abundance was 0.018 sight. km−1and 0.175 ind. km−1. Sightings were concentrated in the Diomboss where relative abundance reached 0.037 sight. km−1and 0.331 ind. km−1. Non-intensive photo-identification produced a minimum population size of 103 animals, the highest recorded forS. teusziianywhere in its range. Photo-identification also confirmed a movement of individuals between different parts of the Saloum Delta. Combined travel–forage dominated the behaviour. Dolphins were photographed capturing mullet (Mugilsp.) on three occasions. The distribution, population size and movements ofS. teusziiare discussed in relation to management. [ABSTRACT FROM AUTHOR]

Mediterranean Sea long-finned pilot whales (Globicephala melas) are currently classified as Data Deficient on the International Union for the Conservation of Nature (IUCN) Red List. Multiple lines of evidence, including molecular genetic and photo-identification mark-recapture analyses, indicate that the Strait of Gibraltar population (distributed from 5.8°W longitude to west of Djibouti Bank and Alborán Dorsal in the Alborán Sea) is differentiated from the Mediterranean Sea population (east of Djibouti Bank and the Alborán Dorsal up to the Ligurian Sea). There is low genetic diversity within the Mediterranean population, and recent gene flow with the Strait of Gibraltar population is restricted. Current total abundance estimates are lacking for the species in the Mediterranean. Pilot whales in the Alborán Sea region were negatively affected by a morbillivirus epizootic from 2006 to 2007, and recovery may be difficult. The Strait of Gibraltar population, currently estimated to be fewer than 250 individuals, decreased by 26.2% over 5 years after the morbillivirus epizootic. Population viability analyses predicted an 85% probability of extinction for this population over the next 100 years. Increasing maritime traffic, increased contaminant burdens, and occasional fisheries interactions may severely impair the capacity of the Strait of Gibraltar population to recover after the decline due to the pathogen. [ABSTRACT FROM AUTHOR]

Sympatric forms of ecologically distinctive killer whales (Orcinus orca) have been documented worldwide. This study focused on a new case of such sympatric occurrence of the "Crozet" type and the recently described "type D" killer whales off the Crozet Islands. The two ecotypes are morphologically and genetically distinct, but they both depredate the same local longline fishery. We used observational, photo-identification, and fishing data, collected between 2003 and 2015, to examine differences in their patterns of depredation. Of the 828 sets where ecotype could be confirmed, type D killer whales interacted with 82 (11%) of the sets, including 9 (1%) sets that were simultaneously depredated by both ecotypes. Associations between the two types were never observed. Type D killer whales typically occurred in larger groups and both ecotypes preferentially depredated Patagonian toothfish (Dissostichus eleginoides). GLMM modeling revealed that the probability of type D depredation significantly increased throughout the study period, especially in deep waters, and photo-identification data suggested that a subset of all individuals were habituating to depredation. This study documents the partitioning of resources between two distinct ecotypes of killer whales and provides preliminary insight into the feeding ecology of the rare type D killer whale. [ABSTRACT FROM AUTHOR]

Photo-identification is used for individual recognition of several animal species. It gives the possibility to take photos of large species from a distance or to avoid invasive marking techniques in small animals. For amphibians, the use of non-invasive marking methods is even more relevant in the light of their global decline. Here we use the photo-identification data from a population of Triturus carnifex to validate the photo-identification software I3S Pattern. This recently developed utility has never been applied to amphibians. The software proved to be efficient and accurate for individual recognition for this species. Contrarily to the previous releases of the I3S family, I3S Pattern is particularly suitable for amphibians characterized by a complex individual pattern of large blotches or irregular spots, which are not readily identified by eye. [ABSTRACT FROM AUTHOR]

The correct identification of individuals is a requirement of capture-mark-recapture (CMR) methods, and it is commonly achieved by applying artificial marks or by mutilation of study-animals. An alternative, non-invasive method to identify individuals is to utilize the patterns of their natural body markings. However, the use of pattern mapping is not yet widespread, mainly because it is considered time consuming, particularly in large populations and/or long-term CMR studies. Here we explore the use of pattern mapping for the identification of adult individuals in the alpine ( Ichthyosaura alpestris) and smooth ( Lissotriton vulgaris) newts (Amphibia, Salamandridae), using the freely available, open-source software Wild-ID. Our photographic datasets comprised nearly 4000 captured animals' images, taken during a 3-year period. The spot patterns of individual newts of both species did not change through time, and were sufficiently varied to allow their individual identification, even in the larger datasets. The pattern-recognition algorithm of Wild-ID was highly successful in identifying individual newts in both species. Our findings indicate that pattern mapping can be successfully employed for the identification of individuals in large populations of a broad range of animals that exhibit natural markings. The significance of pattern-mapping is accentuated in CMR studies that aim in obtaining long-term information on the demography and population dynamics of species of conservation interest, such as many amphibians facing population declines. [ABSTRACT FROM AUTHOR]

Following centuries of exploitation, basking sharks (Cetorhinus maximus) are considered by IUCN as Endangered in the Northeast Atlantic, where they have now been substantially protected for over two decades. However, the present size of this population remains unknown. We investigated the use of photo-identification of individuals’ dorsal fins, combined with mark-recapture methodology, to investigate the size of populations of basking shark within the west coast of Scotland. From a total of 921 encounters photographed between 2004 and 2011, 710 sharks were found to be individually identifiable based on dorsal fin damage and natural features. Of these, only 41 individuals were re-sighted, most commonly both within days of, and close to the site of, the initial encounter. A smaller number were re-sighted after longer periods of up to two years. A comparison of the distinguishing features of individuals on first recording and subsequent re-sighting showed that in almost all cases these features remained little changed, suggesting the low re-sighting rate was not due to a loss of distinguishing features. Because of the low number of re-sighting we were not able to produce reliable estimates for the long-term regional population. However, for one 50 km diameter study area between the islands of Mull, Coll and Tiree, we were able to generate closed-population estimates for 6–9 day periods in 2010 of 985 (95% CI = 494–1683), and in 2011 of 201 (95% CI = 143–340). For the same 2011 period an open-population model generated a similar estimate of 213 (95% CI = 111–317). Otherwise the low rate and temporal patterning of re-sightings support the view that such local basking shark populations are temporary, dynamic groupings of individuals drawn from a much larger regional population than previously supposed. The study demonstrated the feasibility and limitations of photo-identification as a non-invasive technique for identifying individual basking sharks. [ABSTRACT FROM AUTHOR]

Photographic identification (photo-ID) has been increasingly used as a reliable tool to track individuals over time, which provides essential knowledge on a species' population dynamics. For photo-ID to work, natural markings must be individual-specific and stable over time. In sea turtle research, the use of facial scale patterns has been proposed and tested as a reliable means for individual recognition. Nevertheless, as sea turtles are migratory and long-lived individuals, the stability of those patterns over long periods of time is yet to be confirmed to validate this method. Stability of facial scale patterns was evaluated on green sea turtles, Chelonia mydas , sighted and photographed in coastal waters of Reunion Island (21°06 S, 55°36 E) or reared in captivity. From 53 free-ranging individuals previously identified, 90 head profiles were selected based on the photographic quality and the distinctiveness of facial scale patterns. The time interval between two sightings of a same individual ranged from 2 (738d) to 11 years (3954d). Additionally, facial scale patterns of captive green turtles from two different age groups were compared: (1) from adult-sized individuals reared in captivity ( n = 13) and (2) from hatchlings and then at later developmental stages (until 1800d) to assess the stability of facial scale patterns throughout early juvenile development ( n = 16). In both the free-ranging and captive-reared groups, there were no significant changes in facial scale patterns over time. Conversely, changes in pigmentation were observed in free-ranging turtles at successive sightings and in captive-reared turtles at different developmental stages. These results on the stability of facial scale patterns over time, combined with previous findings on the uniqueness of patterns between individual green turtles, validate the method of using facial scale patterns as a long-term identification tool for green turtles. Nonetheless, the variability of pigmentation patterns should be kept in mind when using photo-identification on sea turtle species. [ABSTRACT FROM AUTHOR]

Recognition of individuals within an animal population is central to a range of estimates about population structure and dynamics. However, traditional methods of distinguishing individuals, by some form of physical marking, often rely on capture and handling which may affect aspects of normal behavior. Photographic identification has been used as a less-invasive alternative, but limitations in both manual and computer-automated recognition of individuals are particularly problematic for smaller taxa (<500 g). In this study, we explored the use of photographic identification for individuals of a free-ranging, small terrestrial reptile using (a) independent observers, and (b) automated matching with the Interactive Individual Identification System (I3S Pattern) computer algorithm. We tested the technique on individuals of an Australian skink in the Egernia group, Slater's skink Liopholis slateri, whose natural history and varied scale markings make it a potentially suitable candidate for photo-identification. From 'photographic captures' of skink head profiles, we designed a multi-choice key based on alternate character states and tested the abilities of observers - with or without experience in wildlife survey - to identify individuals using categorized test photos. We also used the I3S Pattern algorithm to match the same set of test photos against a database of 30 individuals. Experienced observers identified a significantly higher proportion of photos correctly (74%) than those with no experience (63%) while the I3S software correctly matched 67% as the first ranked match and 83% of images in the top five ranks. This study is one of the first to investigate photo identification with a free-ranging small vertebrate. The method demonstrated here has the potential to be applied to the developing field of camera-traps for wildlife survey and thus a wide range of survey and monitoring applications. [ABSTRACT FROM AUTHOR]

There has been very little previous research on Indo-Pacific humpback dolphins (Sousa chinensis) in the Beibu Gulf of southern China. Here, we report on the population size, habitat and ecology, threats, and overall conservation status of this putative population. 'Population size' was estimated based on photo-identification mark/recapture analysis. It was estimated to number a total of 398-444 individuals (95% CI: 393-506), with two apparently distinct groups in the Dafengjiang-Nanliujiang Estuary and at Shatian-Caotan. Movements of dolphins in the Beibu Gulf appear to be limited, with high site fidelity. These dolphins were found to occur mainly in shallow coastal waters near estuaries. The main threats are fisheries interactions (including by-catch), vessel traffic, mariculture operations, dolphin-watching tourism, and habitat degradation (including marine construction activities and large-scale land reclamation). Although the conservation status of this putative population has been considered to be better than that of other populations of the species in more northern areas of China, there is still reason for strong concern about its future, and several management recommendations are made. [ABSTRACT FROM AUTHOR]

On 22 February 2015, a single specimen of Carcttn carettn was identified in surface waters about 45 nm west of Tofino, British Columbia. The animal's carapace was covered with algae, but the specimen was identified based on shell shape, head size, and the color of its parietal and interparietal scales. This record confirms that 4 sea turtle species range into British Columbia's coastal waters. [ABSTRACT FROM AUTHOR]

Site-based population estimates of the threatened Glossy Black-Cockatoo ('GBC'; Calyptorhynchus lathami) are often calculated based on age and sex details from transect counts. However, these estimates do not distinguish individual birds, which may result in over-or under-estimation of the population. Two methods were used to estimate GBC populations in Mugii Murum-ban State Conservation Area, New South Wales: (1) the traditional transect method, and (2) a photographic method, which used plumage patterns (primarily the yellow facial feathers of females) and other supporting features to discriminate between foraging GBC family units. The second method has been used previously on Kangaroo Island, South Australia. A catalogue with a matrix of discriminating features was established based on the photographic method; this resulted in a higher population estimate than the transect method in two seasons (winter and spring), as well as providing an annual population estimate, and information on breeding dynamics and local movement of individual family units between foraging habitat. Recommendations for the application of the photographic method are provided. The method provides benefits at both the local scale (with more accurate site population estimates and information on population dynamics) and, with widespread adoption and national cataloguing, valuable knowledge on regional movement patterns and distribution. [ABSTRACT FROM AUTHOR]

Subsurface video footage can be used as a successful identification tool for various marine organisms; however, processing of such information has proven challenging. This study tests the use of automated software to assist with photo-identification of the great white sharkCarcharodon carchariasin the region of Gansbaai, on the south coast of South Africa. A subsurface photo catalogue was created from underwater video footage. Single individuals were identified by using pigmentation patterns. From this catalogue, two images of the head for each individual were inserted into automated contour-recognition software (Interactive Individual Identification System Beta Contour 3.0). One image was used to search the database, the other served as a reference image. Identification was made by means of a contour, assigned using the software to the irregular border of grey and white on the shark's head. In total, 90 different contours were processed. The output provided ranks, where the first match would be a direct identification of the individual. The method proved to be accurate, in particular for high-quality images where 88.24% and 94.12%, respectively, were identified by two independent analysts as first match, and with all individuals identified within the top 10 matches. The inclusion of metadata improved accuracy and precision, allowing identification of even low-quality images. [ABSTRACT FROM AUTHOR]