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Ex situliver machine perfusion at subnormothermic/normothermic temperature isincreasingly applied in the field of transplantation to store and evaluateorgans on the machine prior transplantation. Currently, various perfusionconcepts are in clinical and preclinical applications. Over the last 6 years ina multidisciplinary team, a novel blood based perfusion technology wasdeveloped to keep a liver alive and metabolically active outside of the bodyfor at least one week.Within thismanuscript, we present and compare three scenarios (Group 1, 2 and 3) we werefacing during our research and development (RD) process, mainly linked tothe measurement of free hemoglobin and lactate in the blood based perfusate. Apartfrom their proven value in liver viability assessment (ex situ), these twoparameters are also helpful in RD of a long-term liver perfusion machine and moreover supportive in the biomedical engineering process.Group 1 ("good" liver on the perfusion machine) represents the best liver clearance capacity for lactate and free hemoglobin wehave observed. In contrast to Group 2 ("poor" liver on the perfusion machine), that has shown the worst clearance capacity for free hemoglobin. Astonishingly,also for Group 2, lactate is cleared till the first day of perfusion andafterwards, rising lactate values are detected due to the poor quality of theliver. These two perfusate parametersclearly highlight the impact of the organ quality/viability on the perfusion process. Whereas Group 3 is a perfusion utilizing a blood loop only (without a liver).Knowing the feasible ranges (upper- and lower bound) and the courseover time of free hemoglobin and lactate is helpful to evaluate the quality ofthe organ perfusion itself and the maturity of the developed perfusion device. Freehemoglobin in the perfusate is linked to the rate of hemolysis that indicates how optimizing (gentle blood handling, minimizing hemolysis) the perfusion machine actually is. Generally, a reduced lactate clearancecapacity can be an indication for technical problems linked to the blood supplyof the liver and therefore helps to monitor the perfusion experiments.Moreover, the possibility is given to compare, evaluate and optimize developed liverperfusion systems based on the given ranges for these two parameters. Otherresearch groups can compare/quantify their perfusate (blood) parameters withthe ones in this manuscript. The presented data, findings and recommendations willfinally support other researchers in developing their own perfusion machine ormodifying commercially availableperfusion devices according to their needs.

Objective The aim of this study was to maintain long-term full function and viability of partial livers perfused ex situ for sufficient duration to enable ex situ treatment, repair, and regeneration. Background Organ shortage remains the single most important factor limiting the success of transplantation. Autotransplantation in patients with nonresectable liver tumors is rarely feasible due to insufficient tumor-free remnant tissue. This limitation could be solved by the availability of long-term preservation of partial livers that enables functional regeneration and subsequent transplantation. Methods Partial swine livers were perfused with autologous blood after being procured from healthy pigs following 70% in-vivo resection, leaving only the right lateral lobe. Partial human livers were recovered from patients undergoing anatomic right or left hepatectomies and perfused with a blood based perfusate together with various medical additives. Assessment of physiologic function during perfusion was based on markers of hepatocyte, cholangiocyte, vascular and immune compartments, as well as histology. Results Following the development phase with partial swine livers, 21 partial human livers (14 right and 7 left hemi-livers) were perfused, eventually reaching the targeted perfusion duration of 1 week with the final protocol. These partial livers disclosed a stable perfusion with normal hepatic function including bile production (5-10 mL/h), lactate clearance, and maintenance of energy exhibited by normal of adenosine triphosphate (ATP) and glycogen levels, and preserved liver architecture for up to 1 week. Conclusion This pioneering research presents the inaugural evidence for long-term machine perfusion of partial livers and provides a pathway for innovative and relevant clinical applications to increase the availability of organs and provide novel approaches in hepatic oncology.

Long-term ex situ liver perfusion may rescue injured grafts. Little is known about bile flow during long-term perfusion. We report the development of a bile stimulation protocol and motivate bile flow as a viability marker during long-term ex situ liver perfusion.Porcine and human livers were perfused with blood at close to physiologic conditions. Our perfusion protocol was established during phase 1 with porcine livers (n = 23). Taurocholic acid was applied to stimulate bile flow. The addition of piperacillin-tazobactam (tazobac) and methylprednisolone was modified from daily bolus to controlled continuous application. We adapted the protocol to human livers (n = 12) during phase 2. Taurocholic acid was replaced with medical grade ursodeoxycholic acid.Phase 2: Despite administering taurocholic acid, bile flow declined from 29.3 ± 6.5 to 9.3 ± 1.4 mL/h (P.001). Shortly after bolus of tazobac/methylprednisolone, bile flow recovered to 39.0 ± 9.7 mL/h with a decrease of solid bile components. This implied bile salt independent bile flow stimulation by tazobac/methylprednisolone. Phase 2: Ursodeoxycholic acid was shown to stimulate bile flow ex situ in human livers. Eight livers were perfused successfully for 1 week with continuous bile flow. The other 4 livers demonstrated progressive cell death, of which only 1 exhibited bile flow.A lack of bile flow stimulation leads to a decline in bile flow and is not necessarily a sign of deterioration in liver function. Proper administration of stimulators can induce constant bile flow during ex situ liver perfusion for up to 1 week. Medical grade ursodeoxycholic acid is a suitable replacement for nonmedical grade taurocholic acid. The presence of bile flow alone is not sufficient to assess liver viability.

PURPOSE Ex vivo liver machine perfusion is a promising option to rescue marginal liver grafts mitigating the donated organ shortage. Recently, a novel liver perfusion machine that can keep injured liver grafts alive for 1 week ex vivo was developed and reported in Nature Biotechnology. However, liver viability assessment ex vivo is an unsolved issue and the value of 18F-fluorodeoxyglucose (FDG)-PET/CT for such purpose was explored. MATERIALS AND METHODS Discarded two human and six porcine liver grafts underwent FDG-PET/CT for viability assessment after 1 week of ex vivo perfusion. PET parameters [standardized uptake value (SUV)max, SUVmean, SUVpeak and total lesion glycolysis] were compared between hepatic lobes and between porcine and human livers. The prevalence of FDG-negative organ parts was recorded. The estimated effective radiation dose for PET/CT was calculated. RESULTS All organs were viable with essentially homogeneous FDG uptake. Of note, viability was preserved in contact areas disclosing the absence of pressure necrosis. Four porcine and two human organs had small superficial FDG-negative areas confirmed as biopsy sites. Total lesion glycolysis was significantly higher in the right hepatic lobe (P = 0.012), while there was no significant difference of SUVmax, SUVmean and SUVpeak between hepatic lobes. There was no significant difference in FDG uptake parameters between porcine and human organs. The estimated effective radiation dose was 1.99 ± 1.67 mSv per organ. CONCLUSION This study demonstrates the feasibility of FDG-PET/CT for viability assessment of ex vivo perfused liver grafts after 1 week.

Objective: The hepatic arterial buffer response is a well-known phenomenon in hepatic circulation, describing the response of hepatic arterial resistance to changes in portal vein flow. Several vasoactive metabolites underlying its mechanism have been proposed, however, there is currently no clear consensus. The aim of this study is to investigate the hepatic arterial buffer response of porcine livers preserved in a controlled ex vivo perfusion machine. Methods: Porcine livers are perfused on an ex vivo perfusion machine and hemodynamic experiments investigating the hepatic arterial resistance response to portal vein flow and vena cava pressure variations are conducted. A simple hemodynamic model is developed to support the interpretation of the received measurements. Further, a mechanism is proposed that explains hepatic arterial resistance changes in response to vena cava pressure as myogenic and in response to portal vein flow as a combined washout and myogenic effect. Results: A clear correlation between hepatic sinusoidal pressure levels and hepatic arterial resistance is observed where an increase of approximately 4 mmHg of hepatic sinusoidal pressure level results in doubling of the hepatic arterial resistance. This relation is considered during the analysis of the portal vein flow variations resulting in a reduced isolated effect of adenosine washout on hepatic arterial resistance. With an average buffer capacity of 27% during our experiments, the hepatic arterial buffer response shows to be unimpaired in the ex vivo scenario. Conclusion: First, washout and myogenic effects both influence the hepatic arterial buffer response; and second, hepatic sinusoidal pressure levels strongly influence the hepatic arterial resistance. Significance: These results present new findings in hemodynamics of the liver, which are fundamental for successful ex vivo liver perfusion.

The ability to preserve metabolically active livers ex vivo for 1 week or more could allow repair of poor-quality livers that would otherwise be declined for transplantation. Current approaches for normothermic perfusion can preserve human livers for only 24 h. Here we report a liver perfusion machine that integrates multiple core physiological functions, including automated management of glucose levels and oxygenation, waste-product removal and hematocrit control. We developed the machine in a stepwise fashion using pig livers. Study of multiple ex vivo parameters and early phase reperfusion in vivo demonstrated the viability of pig livers perfused for 1 week without the need for additional blood products or perfusate exchange. We tested the approach on ten injured human livers that had been declined for transplantation by all European centers. After a 7-d perfusion, six of the human livers showed preserved function as indicated by bile production, synthesis of coagulation factors, maintained cellular energy (ATP) and intact liver structure., Livers are stored long term in a sophisticated perfusion system.

The aim of this study was to maintain long-term full function and viability of partial livers perfused ex situ for sufficient duration to enable ex situ treatment, repair, and regeneration.Organ shortage remains the single most important factor limiting the success of transplantation. Autotransplantation in patients with nonresectable liver tumors is rarely feasible due to insufficient tumor-free remnant tissue. This limitation could be solved by the availability of long-term preservation of partial livers that enables functional regeneration and subsequent transplantation.Partial swine livers were perfused with autologous blood after being procured from healthy pigs following 70% in-vivo resection, leaving only the right lateral lobe. Partial human livers were recovered from patients undergoing anatomic right or left hepatectomies and perfused with a blood based perfusate together with various medical additives. Assessment of physiologic function during perfusion was based on markers of hepatocyte, cholangiocyte, vascular and immune compartments, as well as histology.Following the development phase with partial swine livers, 21 partial human livers (14 right and 7 left hemi-livers) were perfused, eventually reaching the targeted perfusion duration of 1 week with the final protocol. These partial livers disclosed a stable perfusion with normal hepatic function including bile production (5-10 mL/h), lactate clearance, and maintenance of energy exhibited by normal of adenosine triphosphate (ATP) and glycogen levels, and preserved liver architecture for up to 1 week.This pioneering research presents the inaugural evidence for long-term machine perfusion of partial livers and provides a pathway for innovative and relevant clinical applications to increase the availability of organs and provide novel approaches in hepatic oncology.

INTRODUCTION The use of normothermic liver machine perfusion to repair injured grafts ex situ is an emerging topic of clinical importance. However, a major concern is the possibility of microbial contamination in the absence of a fully functional immune system. Here, we report a standardized approach to maintain sterility during normothermic liver machine perfusion of porcine livers for one week. METHODS Porcine livers (n = 42) were procured and perfused with blood at 34°C following aseptic technique and standard operating procedures. The antimicrobial prophylaxis was adapted and improved in a step-wise manner taking into account the pathogens that were detected during the development phase. Piperacillin-Tazobactam was applied as a single dose initially and modified to continuous application in the final protocol. In addition, the perfusion machine was improved to recapitulate partially the host's defense system. The final protocol was tested for infection prevention during one week of perfusion. RESULTS During the development phase, microbial contamination occurred in 27 out of 39 (69%) livers with a mean occurrence of growth on 4 ± 1.6 perfusion days. The recovered microorganisms suggested an exogenous source of microbial contamination. The antimicrobial agents (piperacillin/tazobactam) could be maintained above the targeted minimal inhibitory concentration (8-16 mg/L) only with continuous application. In addition to continuous application of piperacillin/tazobactam, partial recapitulation of the host immune system ex situ accompanied by strict preventive measures for contact and air contamination maintained sterility during one week of perfusion. CONCLUSION The work demonstrates feasibility of sterility maintenance for one week during ex situ normothermic liver perfusion.

Andean Cocks-of-the-rock (Rupicola peruvianus; ACOR) are frugivorous, tropical lekking birds iconic to Andean cloud forests. Little is known about ACOR natural history outside of limited studies focused on their lekking behavior and diet. Given the persisting, detrimental effects of cloud forest deforestation, an increased understanding of ACOR natural history is critical for their conservation. Using capture-mark-resight/recapture (CMR) methods on R. p. sanguinolentus in northwest Ecuador, we determined the apparent annual survival of ACOR males and derived estimates for ACOR male longevity. The 2 top models estimated male ACOR apparent annual survival at 0.98 and 0.97, respectively, and our naive estimate of survival was 0.87. Furthermore, we found banded ACOR males could persist at the lek for upwards of 14 years. Our results present key information on ACOR vital rates and offer a framework to understand those of related cotingids. Future studies should prioritize elucidating vital rates for ACOR females as well as specific habitat requirements of ACOR and related cotingids to inform specific conservation plans aimed at protecting these species.

Mutualistic interactions, such as animal pollination, structure biodiversity in the Neotropics. In coastal montane garua (fog) forests of Ecuador, 2 mass-blooming plants attract up to 17 species of nectar-feeding birds, especially hummingbirds. We describe avian guilds and behavior at the 2 mass bloomers and use mist-netting capture rates to test 3 predictions: (1) capture rates of territorial hummingbirds will increase with flower abundance on the mass bloomer they defend, (2) hummingbirds known to mainly use other flowers will show no change in capture rate during mass blooms, and (3) field observations of interspecific interactions will be reflected in capture rates. We statistically modeled capture rates of bird species, species richness, and Shannon Diversity Index in response to flower abundance on the 2 mass bloomers during 16 flowering seasons (1996–2013). Capture rates of 8 nectar-feeding species increased significantly with increased abundance of white-flowered Psychotria hazenii blooms, while only one species, Speckled Hummingbird (Adelomyia melanogenys), increased significantly in response to red-flowered Stenostephanus clarkii flower abundance, and aggressively defended these flower patches. Violet-bellied Hummingbird (Damophila julie) showed the strongest capture rate response to increased abundance of P. hazenii flowers, and was the dominant territorial hummingbird around these shrubs. Endangered Esmeraldas Woodstars (Chaetocercus berlepschi) and Little Woodstars (Chaetocercus bombus) visited both mass bloomers, but had a statistically significant increase only with P. hazenii highest flower abundance suggesting that restoration to recover endangered woodstars will benefit more from plantings of P. hazenii than S. clarkii. We conclude that flower abundance and defendability structure avian pollinator networks at these mass bloomers more so than nectar quality, quantity, or secretion rates, all of which were similar.

Long-term perfusion of liver grafts outside of the body may enable repair of poor-quality livers that are currently declined for transplantation, mitigating the global shortage of donor livers. In current ex vivo liver perfusion protocols, hyperoxic blood (arterial blood) is commonly delivered in the portal vein (PV). We perfused porcine livers for one week and investigated the effect of and mechanisms behind hyperoxia in the PV on hepatic arterial resistance. Applying PV hyperoxia in porcine livers (n = 5, arterial PV group), we observed an increased need for vasodilator Nitroprussiat (285 ± 162 ml/week) to maintain the reference hepatic artery flow of 0.25 l/min during ex vivo perfusion. With physiologic oxygenation (venous blood) in the PV the need for vasodilator could be reduced to 41 ± 34 ml/week (p = 0.011; n = 5, venous PV group). This phenomenon has not been reported previously, owing to the fact that such experiments are not feasible practically in vivo. We investigated the mechanism of the variation in HA resistance in response to blood oxygen saturation with a focus on the release of vasoactive substances, such as Endothelin 1 (ET-1) and nitric oxide (NO), at the protein and mRNA levels. However, no difference was found between groups for ET-1 and NO release. We propose direct oxygen sensing of endothelial cells and/or increased NO break down rate with hyperoxia as possible explanations for enhanced HA resistance., Scientific Reports, 10 (1), ISSN:2045-2322

Objective: With the growing demand for livers in the field of transplantation, interest in normothermic ex situ machine perfusion (NMP) has increased in recent years. This may open the door for novel therapeutic interventions such as repair of suboptimal grafts. For successful long-term NMP of livers, blood glucose (BG) levels need to be maintained in a close to physiological range. Methods: We present an “automated insulin delivery” (AID) system integrated into an NMP system, which automatically adjusts insulin infusion rates based on continuous BG measurements in a closed loop manner during ex situ pig and human liver perfusion. An online glucose sensor for continuous glucose monitoring was integrated and evaluated in blood. A model based and a proportional controller were implemented and compared in their ability to maintain BG within the physiological range. Results: The continuous glucose sensor is capable of measuring BG directly in human and pig blood for multiple days with an average error of 0.6 mmol/L. There was no significant difference in the performance of the two controllers in terms of their ability to keep BG in the physiological range. With the integrated AID, BG was controlled within the physiological range on average in 80% and 76% of the perfusion time for human and pig livers, respectively. Conclusion: The presented work offers a method and shows the feasibility to maintain BG in the physiological range for multiple (up to ten) days during ex situ liver perfusion with the help of an automated AID. Significance: Maintaining BG within the physiological range is required to enable long-term ex situ liver perfusion.

Electrochemical micro-probes are used to study the flow regime and liquid–solid mass transfer inside a designed porous structure. In order to place the electrodes inside the porous structure avoiding gluing and polishing, the electrodes are glued flush with pins. These pins are then simply plugged into the structure. In a first step, the influence of the pin on the local flow behavior is studied. It is shown, that the departure from the laminar flow regime can be determined within 10% accuracy in empty pipes. Additionally, the influence of the pin length on the point of transition is studied inside the porous structure showing errors below 10% for pin lengths with an accuracy of ±0.5 mm. In a second step, the flow regime is determined with a simple algorithm, allowing a reproducible detection of the laminar plateau and the onset of fluctuations. The departure from the laminar regime is found at Re lam , end = 162 ± 3 . In the third and last step, the liquid–solid mass transfer is studied for a single-phase liquid flow and gas–liquid two-phase flow. It is shown, that the second phase is enhancing the mass transfer at low volumetric transport fractions but degrading the mass transfer at volumetric transport fractions higher than 6%. The Sherwood number is compared to the literature and correlations are presented to describe the Sherwood number in the laminar and turbulent flow regime.

Maui Parrotbills (Pseudonestor xanthophrys), critically endangered Hawaiian honeycreepers endemic to the island of Maui, are restricted to a single population of ∼500 individuals located in remote, mountainous terrain. From January to June 2006-2011, we located nests and fledglings in the Hanawi Natural Area Reserve (NAR) in east Maui, Hawaii, to document nest success and annual reproductive success. Nest success is a commonly used measure of productivity and is a central component of many demographic studies. Annual reproductive success is less frequently documented because greater effort is required to monitor the reproductive successofbreedingpairsthroughtime.However,forspecieswhosenestsaredifficulttolocateoraccess,suchasMaui Parrotbills, the presence or absence of fledged young may provide a more accurate measure of breeding success than monitoring nests. During our study, we located and determined the outcome of 30 nests to document nest success, and monitored 106 territories for the presence or absence of fledglings to calculate annual reproductive success. Nest success probability was 19% (N = 30) and seasonal nest success was 46%. During our monitoring efforts, 49 of 106 breeding pairs produced a single fledged young. Because parrotbills typically have single egg clutches and only re-nest after nests fail, the presence or absence of a fledgling is an indication of a pair's overall reproductive success for a breeding season. Based on the number of fledglings per pair, our estimate of annual reproductive success was 46%, confirming our initial productivity estimate from nests. Thus, our results indicate that the two methods, determining annual reproductive success by monitoring fledglings and calculating nest success, provide similar estimates of annual productivity for Maui Parrotbills. Based on our estimates, the parrotbill population appears to be demographically stable. However, our productivity estimate was based only on the population at Hanawi, an area representing just 3% of the total range of parrotbills. Thus, our results may not accurately reflect the status of parrotbills over their entire range.

The Critically Endangered (IUCN) Maui parrotbill Pseudonestor xanthophrys, an endemic Hawaiian honeycreeper, is restricted to a single population of about 500 individuals. During 3 breeding seasons (2006 to 2008) we found and monitored 17 Maui parrotbill nests from 13 pairs. Eggs and incubating females were confirmed for 12 of the nests, but only 4 fledged successfully. Severe weather led to nest abandonment in 5 cases. Two nests were depredated, and 1 nest had an egg that failed to hatch. Three pairs renested after failures. We used logistic linear regression and ANOVA to evaluate 300 h of observations to assess the effects of parental investment behavior and weather on nest fate. Female time incubating, a significant factor explaining nest fate, did not differ by time of day, but averaged 12 min h -1 less for failed than for successful nests. Male provisioning rates to adult females and chick feeding rates by parents were also significantly related to nest suc- cess. Male vocalizations near the nest did not differ by nest fate. Establishment of a second popula- tion is a key step in the recovery of Maui parrotbills, and a small captive population has been estab- lished. Although limited, our data suggest that collection of Maui parrotbill eggs and/or nestlings up to 1 wk old from nests for captive rearing, especially in advance of severe winter storms, would have minimal effects on the population.

Large-scale transformation of forested landscapes is a major factor in loss of biological diversity in the American tropics. Investigators examining the responses of species to deforestation rarely control for variation in the amount of forest relative to other habitats at the landscape-level. Bellavista Reserve on the western slope of the Andes in Ecuador is located between similar-sized areas of pristine, protected forest, and deforested landscapes. We used strip-transect counts and mist netting to evaluate habitat use by passerine birds in a habitat mosaic consisting of abandoned pastures, forest edges, forest fragments, and large blocks of interior tropical montane cloud forest (TMCF). During 3600 net hours, we had 1476 captures, including 346 recaptures. Of 78 species captured in mist nets, 30 had sufficient counts for Poison Rate Regression (PRR) modeling (a statistical method for comparing counts). Twelve species (40%) had capture patterns indicative of an affinity for mature TMCF, and 6 species (20%) had significantly higher counts in degraded areas (forest edge, forest fragment, and regenerating pastures) than in interior TMCF. The remaining 40% showed no significant bias in detection among habitats. Combined with strip-count data, our results suggest that about 38% of the 119 species sampled at the Bellavista Reserve occur primarily in mature TMCF, avoiding edges and early second-growth forest. Populations of these species may be vulnerable to further loss, fragmentation, and degradation of TMCF and, as such, deserve additional study and a place on lists of species of conservation concern. SINOPSIS Las transformaciones a larga escala del paisaje de bosques es un factor principal en la perdida de biodiversidad biologica en los tropicos de america. Los investigadores que examinan la respuesta de especies a la deforestacion, raras veces controlan las variaciones en la cantidad de bosque, relativa a otros habitats a nivel del paisaje. La Reserva Bellavista, que se encuentra en la pendiente oeste de los Andes ecuatorianos, se encuentra localizada entre areas (de similar tamano), pristinas de bosques protegidos y areas deforestadas. Utilizamos transectos lineares y capturas con redes de niebla para evaluar el uso de habitat, por parte de paserinos, en un mosaico de habitats que consistio de tierras de pastoreo abandonadas, bordes de bosques, fragmentos de bosques y grandes bloques de bosque montano tropical nuboso (BMTN). En 3600 horas de trabajo, capturamos 1476 aves, incluyendo 346 recapturas. De 78 especies capturadas con redes de niebla, en 30 tuvimos el numero suficiente para aplicarle el metodo estadistico PRR. Doce especies (40%) tuvieron un patron de captura asociado al BMTN, y seis especies (20%) tuvieron un conteo significativamente mayor en areas degradadas (bordes, fragmentos y areas de pastizales en estado de regeneracion) que en el BMTN. El restante 40% no mostro sesgo significativo de detectabilidad entre los diferentes tipos de habitats. Al combinar las capturas con los transectos, nuestros resultados sugieren que un 38% de las 119 especies muestreadas ocurren particularmente en el BMTN maduro, evitando bordes y etapas tempranas de sucesion. Las poblaciones de estas especies pudieran ser vulnerables a mayor perdida de bosque, a la fragmentacion o degradacion de los BMTN. Las mismas ameritan mas estudios y deben colocarse en la lista de aves cuya conservacion amerite preocupacion.

To reveal more clearly the places that are critical for generating and sustaining species diversity, the distribution of genetic diversity is informative for conservation. Evolutionary significant units (ESUs) represent distinct lineages within a species and are defined by genetic and morphological differences. We examine morpho- metrics and mitochondrial DNA sequences of two coastal and three Andean populations of Gray-breasted Wood Wrens (Henicorhina leucophrys) in Ecuador to determine if any populations are ESUs. Coastal Wood Wrens diverged genetically by 2.4%, 3.5%, and 4.4% from Andean populations of the northwest (Bellavista), southwest (Sural- Caucha), and southeast (Romerillos), respectively. The five populations (34 individuals) exhibited nine haplotypes. Both genetic and ecological results indicate that coastal Wood Wrens found in the Colonche Hills are ESUs, as are the Andean populations. In contrast with temperate regions, where large reserves connected by corridors may be effective, preservation of biodiversity in tropical South America may require protection of more localized areas. SINOPSIS. Haplotipos en el ADN mitocondrial, divergencia en su secuencia y variaci´ on morfol´ ogica en Henichorina leucophrys, e implicaciones para la consevaci´ on

Monitoring of fog capture and bird communities helped to build social capital for conservation at Loma Alta, Ecuador and encouraged the local community to protect 3000 hectares of tropical forest. Data collected during monitoring were used to facilitate action and cooperation at local, regional, national, and international levels for conservation of biodiversity in western Ecuador, including the designation of an Important Bird Area in the region. Through involvement with the monitoring efforts, local people became more aware of the value of ecosystem services, learned about local birds and their conservation status, became familiar with ecotourism, and began to include conservation of biodiversity with sustainable development planning in their community. The context of monitoring, the objectives and participants, field methods, impacts in terms of conservation action, and the costs and benefits of the two monitoring initiatives are described.

Concerns about forest fragmentation and its conservation implications have motivated numerous studies that investigate the influence of forest patch area and forest edge on songbird distribution patterns. The generalized effects of forest patch size and forest edge on animal distributions is still debatable because forest patch size and forest edge are often confounded and because of an incomplete synthesis of available data. To fill a portion of this gap, we incorporated all available published data (33 papers) in meta-analyses of forest edge and area effects on site occupancy patterns for 26 Neotropical migrant forest-nesting songbirds in eastern North America. All reported area effects are confounded or potentially confounded by edge effects, and we refer to these as “confounded” studies. The converse, however, is not true and most reported edge effects are independent of patch area. When considering only nonconfounded studies of edge effects, only 1 of 17 species showed significant edge avoidance and 3 had significant affinity for edges. In confounded studies, 12 of 22 species showed significant avoidance of small patches and edges, and 1 had an affinity for small patches and edges. Furthermore, average effect sizes averaged across studies or species tended to be higher for confounded studies than for edge studies. We discuss three possible reasons for differences in results between these two groups of studies. First, studies of edge effects tended to be carried out in landscapes with greater forest cover than studies of confounded effects; among confounded effects studies, as forest cover increased, we observed a nonsignificant trend towards decreasing strength of small patch or edge avoidance effects. Thus, the weaker effects in edge studies may be due to the fact that these studies were conducted in forest-dominated landscapes. Second, we may have detected strong effects only in confounded studies because area effects are much stronger than edge effects on bird occurrence, and area effects drive the results in confounded studies. Third, edge and area effects may interact in such a way that edge effects become more important as forest patch size decreases; thus, both edge and area effects are responsible for results in confounded studies. These three explanations cannot be adequately separated with existing data. Regardless, it is clear that fragmentation of forests into small patches is detrimental to many migrant songbird species. Resumen: La preocupacion sobre la fragmentacion de bosques y sus implicaciones en conservacion ha motivado numerosos estudios que investigan la influencia del area de parches de bosque sobre los patrones de distribucion de aves canoras. Los efectos generalizados del tamano del parche y del borde de bosque sobre la distribucion de animales aun son debatibles porque el tamano y borde a menudo son confundidos y porque la sintesis de los datos disponibles es incompleta. Para llenar parte de este hueco, incorporamos todos los datos disponibles publicados (33 articulos) sobre meta analisis de los efectos de borde y area sobre los patrones de ocupacion de sitios de 26 especies de aves canoras migratorias Neotropicales que anidan en bosques del este de Norte America. Todos los efectos de area estan enmascarados o potencialmente enmascarados por los efectos de borde, y nos referimos a estos como estudios “enmascarados.” Sin embargo, lo contrario no es verdad y la mayoria de los efectos de borde reportados son independientes del area del parche. Al solo considerar estudios de efectos de borde no enmascarados, solo 1 de 17 especies mostro evasion significativa del borde y 3 tenian afinidad significativa por los bordes. En estudios enmascarados, 12 de 22 especies mostraron evasion significativa de parches pequenos y bordes, y 1 tenia afinidad por parches pequenos y bordes. Mas aun, el promedio del tamano de parche promediado para los estudios o especies tendia a ser mayor en los estudios enmascarados que en los estudios de borde. Hablamos tres posibles razones para la diferencias en resultados entre estos dos grupos. Primero, hubo una tendencia a efectuar los estudios de efectos de borde en paisajes con mayor cobertura forestal que los paisajes de estudios de efectos enmascarados; entre los estudios de efectos enmascarados, a medida que incremento la cobertura forestal observamos una tendencia no significativa hacia la disminucion en los efectos de parche pequeno o evasion de borde. Por lo tanto, los efectos mas debiles en estudios de borde pueden deberse al hecho de que estos estudios se llevaron a cabo en paisajes dominados por bosques. Segundo, pudimos haber detectado efectos fuertes solo en estudios enmascarados porque los efectos de area son mucho mas fuertes que los efectos de borde sobre la ocurrencia de las aves, y los efectos de area guian los resultados en estudios enmascarados. Tercero, los efectos de borde y de area pueden interactuar de tal manera que los efectos de borde son mas importantes a medida que decrece el tamano del parche de bosque; por lo tanto, tanto los efectos de borde como de area son responsables de los resultados en estudios enmascarados. Estas tres explicaciones no se pueden separar correctamente con los datos existentes. No obstante, es claro que la fragmentacion de bosques es perjudicial para muchas especies de aves canoras migratorias.

Yellow and red feathers pigmented by carotenoids can signal a bird's condition and are important to both female choice and male-male competition. Melanin-based ornaments are thought to be less effective than carotenoid ornaments as indicators of condition, though their signal function is still relatively unstudied. We examined both carotenoid and melanin-pigmented feather ornaments in a single species, the Kentucky Warbler (Oporornis formosus). Both males and females of this species have melanin-pigmented ornamentation (black crown, black face) and carotenoid-pigmented ornamentation (lemon-yellow undersides). Melanin-pigmented plumage patches were larger in males than females, and males had brighter breast plumage, with a larger ultraviolet component, than females. Among males in the wild, individuals in better condition had more extensive black caps and faces, but not brighter-yellow breasts. Males with larger black caps were more likely to attract mates. This work demonstrates that, in a species with both melanin- and carotenoid-pigmented plumage, melanin-pigmented ornaments can signal condition, and that a melanin-based signal can explain variance in mating success. ¿Funcionan Como Indicadores de la Condición Física y Predicen del Éxito de Apareamiento los Ornamentos del Plumaje Pigmentados con Melanina o Carotenoides en Oporornis formosus? Resumen. Las plumas amarillas y rojas pigmentadas por carotenoides pueden indicar la condición de un ave y son importantes tanto para la elección de machos por parte de las hembras como para la competencia entre machos. Se cree que los ornamentos a base de melanina son menos efectivos como indicadores de condición que los ornamentos carotenoides, aunque su función como señal ha sido menos estudiada. Examinamos plumas ornamentales pigmentadas con carotenoides y melanina en la especie Oporornis formosus. Tanto el macho como la hembra presentan ornamentación pigmentada con melanina (corona negra, rostro negro) y ornamentación pigmentada con carotenoides (flancos inferiores amarillo-limón). Los parches de plumaje pigmentados con melanina fueron mayores en los machos que en las hembras y el plumaje del pecho de los machos fue más brillante y con un componente ultravioleta mayor que el de las hembras. Entre los machos en ambiente natural, los individuos con mejor condición tuvieron coronas y rostros negros más extensos, pero no tuvieron pechos amarillos más brillantes. Los machos con coronas negras más extensas tuvieron una mayor probabilidad de atraer parejas. Este trabajo demuestra que en una especie con plumaje pigmentado con melanina y carotenoides, los ornamentos pigmentados con melanina pueden señalar la condición de los individuos, y que una señal con base en melanina puede explicar la varianza en el éxito reproductivo.

What social arrangements stop deforestation? This paper chronicles the sociological factors underlying the rapid establishment, in 14 months, of a community-owned protected forest in Ecuador. Methods developed by the International Forestry Resources and Institutions (IFRI) research program provide a stakeholder analysis related to trends in deforestation. Interviews, community meetings, and informal discussions provide data on attitudes of local people during and after establishment of the forest preserve. Knowledge and resources external to the community motivated local people to preserve a cloud forest, but local institutions and communal land tenure were critical for the rapid establishment of the protected area.

We define the concept of a common-pool resource based on two attributes: the difficulty of excluding beneficiaries and the subtractability of use. We present similarities and differences among common-pool resources in regard to their ecological and institutional significance. The design principles that characterize long-surviving, delicately balanced resource systems governed by local rules systems are presented, as is a synthesis of the research on factors affecting institutional change. More complex biological resources are a greater challenge to the design of sustainable institutions, but the same general principles appear to carry over to more complex systems. We present initial findings from pilot studies in Uganda related to the effects of institutions on forest conditions.

Early detection of forest degradation may help to compensate for the time-lag that often exists between recognition of poor stewardship and the policy-changes required to mitigate such negative impacts. We report here on an International Forestry Resources and Institutions (IFRI) pilot study in Uganda.

During three breeding seasons, variation in the timing of estrus was monitored in wild red squirrels (Tamiasciurus hudsonicus) in a jack pine forest in central Alberta. The proximate environmental factors that affect the timing of the onset of the breeding season in female squirrels, and variation in dates of estrus, were studied in parallel laboratory and field manipulations. Wild squirrels given ad libitum sunflower seed experienced a positive energy balance (weight gains) earlier in the season than did females on a normal diet. Seed addition advanced dates of estrus by an average of 3 weeks. Three potential cuing mechanisms for the seasonal onset of estrus were proposed and tested: onset of estrus is cued by (i) a simple response to net energy gain, (ii) an interaction between an endogenous circannual rhythm and net energy gain, or (iii) an interaction between annual changes in photoperiod and net energy gain in the absence of a circannual rhythm. Our results refute the first and third mechanisms, and support the idea that red squirrels have a circannual reproductive cycle entrained by photoperiod. Net energy gain interacts with this annual cycle to fine tune the time of ovulation. In laboratory experiments, female squirrels exposed to increasing day length experienced estrus within the normal season. Squirrels kept in constant short-day conditions (

Mother-infant interactions and patterns of foal behaviour in the Grevy's zebra, Equus grevyi , differe from those reported for other equids. Grevy's zebra foals exhibit longer intervals between suckling bouts, do not drink water until they are 3 months old, and reach independence from the mare sooner than other equids. Furthermore, Grevy's zebra foals advance their acquisition of adult feeding behaviour. A 6-week-old Grevy's zebra foal spends as much time feeding as a 5-month-old wild horse foal. From the time their foals are born until the foals reach an age of 3 months, females form small groups (three females and their foals). These groups are never found further than 2·0 km from surface water and are usually associated with a territorial male. Unlike other equids, the foals of which always follow their mares, when female Grevy's zebra go to drink, they leave their foals in ‘kindergartens’, which are guarded by a single adult animal, usually a territorial male. It is proposed that many of these differences in behaviour and rates of juvenile development are the result of adaptation to an arid environment. Water requirements during early lactation appear to influence strongly the social behaviour of the Grevy's zebra and should also be a strong influence on the mother-infant behaviour of other arid-living ungulates.

Meeting the desires of individuals while sustaining ecological "public goods" is a central challenge in natural resources conservation. Indigenous communities routinely make common property decisions balancing benefits to individuals with benefits to their communities. Such traditional knowledge offers insight for conservation. Using surveys and field observations, this case study examines aspects of indigenous institutions and ecological knowledge used by rural Ecuadorians to manage a forest commons before and after interacting with two U.S.-based conservation NGOs: Earthwatch Institute and People Allied for Nature. The rural farming community of Loma Alta has legal property rights to a 6842-ha watershed in western Ecuador. This self- governing community curtailed destruction of their moist forest commons, but not without the influence of modern scientific ecological knowledge. When Earthwatch Institute scientists provided evidence that forest clearing would reduce water supply to the community, villagers quickly modified land allocation patterns and set rules of use in the forest establishing the first community-owned forest reserve in western Ecuador. This case demonstrates that synergy between traditional knowledge and western knowledge can result in sustaining both ecosystem services and biodiversity in a forest commons.

Age at first reproduction influences lifetime reproductive success of individuals and growth rates of populations, and is thus of general interest to ecologists. In red squirrel (Tamiasciurus hudsonicus) populations, yearlings and older nulliparous females (age two and above) are less likely to have a litter than multiparous females (i.e. those that have bred before). To explain these life history traits we tested several hypotheses for why particular females fail to breed in a given year. In a five-year study of red squirrels in a jack pine (Pinus banksiana) forest in central Alberta, Canada, the probability of primiparity (i.e. producing a litter for the first time) was correlated with cone crop size, but doubling the caches of cones available to females failed to increase the probability of first time reproduction. Cones were never completely depleted on any territory, so first reproduction rarely appeared to be restricted by absolute food availability on a territory. We hypothesize, that first reproduction is constrained by the squirrel's ability to obtain seed energy enclosed in serotinous cones that vary in distribution on a territory. We found that the probability of primiparity is lower and more variable between years than that of multiparity, because foraging and cone-handling efficiencies vary more in younger than in older squirrels. Nulliparous females given sunflower seeds to reduce handling time were two to six times more likely to produce a first litter than controls extracting seed from jack pine cones. Small body size, inexperience with seed extraction from serotinous cones, and a lack of strategies for gathering and using cones from a new territory are supported as mechanisms that constrain primiparity, especially in yearlings. Cold spring temperatures added a further constraint in one year, as did absolute cone crop size. Multiparous females strip the bracts off cones in the autumn, reducing handling costs in winter and spring, while young nulliparous females lacked such behavioural compensation. In jack pine, reproductive success of red squirrels depends upon behaviour adapted to a seed supply that is abundant but costly to extract from serotinous cones.

Summary The distribution and abundance of bird species along the Omo River in southwestern Ethiopia were recorded during October and November 1984. The 800 kilometre river ‘transect’ was divided into four sections defined by vegetation, geology, river quality and altitude. Bird populations in each section were treated as temporal communities and census results were analysed for patterns in species richness, taxonomic mix and percentages of ‘widespread’ and ‘local’ species. Results suggest that community gradients exist for bird populations along the river system. In certain bird families, species were added along the gradient. In others, one species seemed to replace another or was correlated with a decrease in abundance of a similar species in the same family. Species diversity and abundance of birds increased along the river. This trend was most notable in the heron and kingfisher families. This preliminary research suggests that bird populations along the Omo River have patterns of distribution and abundance suitable for the study of complex gradients. By conducting species counts along other rivers, a better understanding of this aspect of community ecology may be gained. RESUMEE La distribution et le nombre d'especes d'oiseaux ont ete releves le long de la riviere Omo, dans le sud-ouest de l'Ethiopie, en octobre et novembre 1984. Le secteur de la riviere, long de 800 km, a ete partage en 4 troncons caracterises par la vegetation, la geologie, la qualite de la riviere et l'altitude. Les populations d'oiseaux dans chaque troncon furent considerees comme des communautes temporaires et les resultats des recensements furent etudies aux points de vue de la richesse en especes, de leur melange et du pourcentage d'especes locales et ubiquistes. Les resultats montrer-aient qu'il existe des gradients dans les communautes d'oiseaux le long de la riviere. Dans certaines families d'oiseaux, les especes s'ajoutaient les unes aux autres selon l'endroit. Dans d'autres, une espece semblait en remplacer une autre, out sa presence semblait relieea la diminution d'une espece similaire de la měme famille. La diversite et l'abondance des especes augmentaient au long de la riviere. Cette tendance etait plus sensible dans les families de herons et de martins-pěcheurs. Cette recherche preliminaire suggere que les populations d'oiseaux le long de la riviere Omo ont un schema de distribution et d'abundance interessant pour mener une etude de gradients complexes. Effectuer des comptages sur d'autres rivieres pourrait amener une meilleure comprehension dans l'ecologie des communautes.