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Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Population‐level, historical studies can provide insights on the distribution, abundance and demographic characteristics of imperiled species prior to human exploitation, habitat modification or climate change. These studies provide a baseline for contemporary data, which often shape successful management and recovery.The smalltooth sawfish (Pristis pectinata) occupies ~20% of its historical range due to declines driven primarily by mortalities in fisheries and coastal habitat loss over the last century. As a result, they are listed as Critically Endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species and as Endangered federally in the United States (U.S.).Because P. pectinata grow to a large size and have a toothed rostrum, many historical photographs and specimens are archived in natural history collections. Metadata and morphometric data were collected and analysed from P. pectinata photographs (n = 84) and specimens (n = 429) to evaluate temporal changes in average size and historical distribution of five age classes in U.S. waters.Historically, smaller age classes were well‐distributed throughout the northern Gulf of Mexico, while only larger age classes were recorded on the U.S. east coast, north of Florida. All age classes were found in both Florida and Texas historically, but records from Texas decline after the 1980s and remain persistent in Florida, indicative of a strong‐hold for the U.S. population. Regardless of origin, individuals in three of the five age classes were larger on average historically than those observed today.Understanding which age classes used previously occupied areas will help direct habitat restoration efforts and support recovery, especially in the face of climate change. Non‐traditional data sources, such as those used here, may often be the only means of providing historical context to modern research on imperiled species, ultimately guiding restoration and conservation efforts. [ABSTRACT FROM AUTHOR]

The threatened mint Florida skullcap (Scutellaria floridana) is endemic to four counties in the Florida panhandle. Because development and habitat modification extirpated several historical occurrences, only 19 remain to date. To inform conservation management and delisting decisions, a comprehensive investigation of the genetic diversity and relatedness, population structure, and clonal diversity was conducted using SNP data generated by ddRAD. Compared with other Lamiaceae, we detected low genetic diversity (HE = 0.125–0.145), low to moderate evidence of inbreeding (FIS = −0.02–0.555), and moderate divergence (FST = 0.05–0.15). We identified eight populations with most of the genetic diversity, which should be protected in situ, and four populations with low genetic diversity and high clonality. Clonal reproduction in our circular plots and in 92% of the sites examined was substantial, with average clonal richness of 0.07 and 0.59, respectively. Scutellaria floridana appears to have experienced a continued decline in the number of extant populations since its listing under the Endangered Species Act; still, the combination of sexual and asexual reproduction may be advantageous for maintaining the viability of extant populations. However, the species will likely require ongoing monitoring, management, and increased public awareness to ensure its survival and effectively conserve its genetic diversity. [ABSTRACT FROM AUTHOR]

Ecosystems are degrading world‐wide, with severe ecological and economic consequences. Restoration is becoming an important tool to regain ecosystem services and preserve biodiversity. However, in harsh ecosystems dominated by habitat‐modifying organisms, restoration is often expensive and failure prone. Establishment of such habitat modifiers often hinges on self‐facilitation feedbacks generated by traits that emerge when individuals aggregate, causing density‐ or patch size‐dependent establishment thresholds. To overcome these thresholds, adult or juvenile habitat‐forming species are often transplanted in clumped designs, or stress‐mitigating structures are deployed. However, current restoration approaches focus on introducing or facilitating a single life stage, while many habitat modifiers experience multiple bottlenecks throughout their life as they transition through sequential life stages.Here, we define and experimentally test 'life cycle informed restoration', a restoration concept that focuses on overcoming multiple bottlenecks throughout the target species' lifetime. To provide proof of concept, and show its general applicability, we carried out complementary experiments in intertidal soft‐sediment systems in Florida and the Netherlands where oysters and mussels act as reef‐building habitat modifiers. We used biodegradable structures designed to facilitate bivalve reef recovery by both stimulating settlement with hard and fibrous substrates and post‐settlement survival by reducing predation.Our trans‐Atlantic experiments demonstrate that these structures enabled bivalve reef formation by: (a) facilitating larval recruitment via species‐specific settlement substrates, and (b) enhancing post‐settlement survival by lowering predation. In the Netherlands, structures with coir rope most strongly facilitated mussels by providing fibrous settlement substrate, and predation‐lowering spatially complex hard attachment substrate. In Florida, oysters were greatly facilitated by hard substrates, while coir rope proved unbeneficial.Synthesis and applications. Our findings demonstrate that artificial biodegradable reefs can enhance bivalve reef restoration across the Atlantic by mimicking emergent traits that ameliorate multiple bottlenecks over the reef‐forming organism' life cycle. This highlights the potential of our approach as a cost‐effective and practical tool for nature managers to restore systems dominated by habitat modifiers whose natural recovery is hampered by multiple life stage‐dependent bottlenecks. Therefore, investment in understanding how to achieve life cycle informed restoration on larger scales and whether the method it is applicable to restore other ecosystems is now required. [ABSTRACT FROM AUTHOR]

Urbanization significantly alters habitats for arboreal species, increasing the frequency of very smooth substrates by substituting artificial objects, such as metal poles and painted walls, for some trees. Because they experience these novel substrates more often, urban animals may use strategies to overcome challenges from substrate smoothness that animals from natural habitats do not. We assessed locomotor performance and two-dimensional hindlimb kinematics of two species of Anolis lizards (Anolis cristatellus and Anolis sagrei) from both urban and natural habitats in Miami, Florida. We ran lizards on six racetracks, crossing three substrates of increasing smoothness (rough bark, concrete blocks, and smooth, unpainted wood) with two inclinations (37° and vertical). We found that on vertical tracks with smooth substrates, lizards ran slower, took shorter strides and exhibited more contracted limb postures at the end of their stance than when running on the inclined track. Urban lizards, which are likely to be exposed more often to smooth substrates, did not adjust their movement to increase performance relative to lizards from natural habitats. This result, and the similarity of kinematic strategies between the two species, suggests the locomotor responses of lizards to substrate properties are highly conserved, which may be a mitigating factor that dampens or obviates the effects of natural selection on locomotor behaviour. [ABSTRACT FROM AUTHOR]

A model of the mosquito-mangrove basin ecosystem is presented detailing the habitat of the saltwater mosquito Aedes vigilax utilizing mangrove basin forests in Australia. The modeling included a synthesis of empirical observations and published descriptions including the insect's relevant life-stages, mangrove basin topography and hydrodynamics. Shallow mangrove basins periodically connected by only the highest 10% of high tides with a hummocky substrate micro-topography characterize the main mangrove form conducive to Ae. vigilax breeding. Other essential features include the synchronization of the mosquito's lifecycle to basin hydrodynamics and thus an intricate relationship between hydrodynamics and basin structure. Very small decreases in basin water level (~1 cm/day) lead to significant decreases in extent of standing water (for example, 60% over 6 days) across the basin. This results in corresponding increases in the extent of exposed substrate. Also, the modeling demonstrated sensitivity of the mosquito-mangrove basin ecosystem to sea level changes. A hydrologic model of the basin was used to predict mosquito breeding episodes which were tested against a mosquito management larviciding program. The model predicted 75% of all 29 larviciding treatments undertaken. Comparing the model against the two triggers used by mosquito control, tides and rainfall, the model predicted 92% of tidally instigated treatments and 60% of rainfall instigated treatments. Application of the model enables consideration of environment-based minimal habitat modification for mosquito control in mangroves, not previously possible. The model will be applicable to similar species, such as Ae. taeniorhynchus, found in Florida's (USA) mangroves. [ABSTRACT FROM AUTHOR]

The Loxahatchee River, a 500 km2 watershed on the southeast Florida coast, is a barrier-impounded drowned river valley experiencing rapid urbanization during the past 50 years. The estuary is currently composed of a sandy central basin with bifurcating forks accumulating organic-rich muddy sands. The Northwest Fork drains natural forest, residential, and agricultural catchments and has a much larger bayhead delta than the channelized Southwest Fork, which is only 50 years old and diverts much of the flow from the Northwest Fork. Sediment accumulation rates within muddy sand deposits are about 2-3 mm a-1, commensurate within error of the current rate of local sea-level rise. Previously established Holocene accumulation rates are close to relative sea-level rise, implying that sediment accumulation is in equilibrium with the creation of accommodation space. The main anthropogenic influences have been changes in surface sediment texture corresponding to dredging-induced modification of tidal currents and a localized>threefold increase in sediment accumulation rate supplied by sources local to the estuary. Late Holocene sedimentation has been episodic, and lithofacies vary from bioturbated transgressive sands at depth to peat and laminated fine-grained sediments then back to mottled muddy sands in the uppermost strata. This facies transition is attributed to a change of water column stratification conditions caused by decreased tidal flushing in the estuary possibly brought about by variation in sea level or episodic inlet closure by littoral sand transport. The magnitude of the anthropogenic changes in sedimentation is roughly equal with natural changes in lithofacies formation. [ABSTRACT FROM AUTHOR]

Evaluates the abundance of largemouth bass Micropterus salmoides before and after a habitat enhancement project at Lake Kissimmee, Florida. Factors behind the degradation of fish habitat; Estimation of the age frequencies of largemouth bass; Improvement in the electrofishing catch rates of largemouth bass.