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Humans did not arrive on most of the world's islands until relatively recently, making islands favorable places for disentangling the timing and magnitude of natural and anthropogenic impacts on species diversity and distributions. Here, we focus on Amazona parrots in the Caribbean, which have close relationships with humans (e.g., as pets as well as sources of meat and colorful feathers). Caribbean parrots also have substantial fossil and archaeological records that span the Holocene. We leverage this exemplary record to showcase how combining ancient and modern DNA, along with radiometric dating, can shed light on diversification and extinction dynamics and answer long-standing questions about the magnitude of human impacts in the region. Our results reveal a striking loss of parrot diversity, much of which took place during human occupation of the islands. The most widespread species, the Cuban Parrot, exhibits interisland divergences throughout the Pleistocene. Within this radiation, we identified an extinct, genetically distinct lineage that survived on the Turks and Caicos until Indigenous human settlement of the islands. We also found that the narrowly distributed Hispaniolan Parrot had a natural range that once included The Bahamas; it thus became "endemic" to Hispaniola during the late Holocene. The Hispaniolan Parrot also likely was introduced by Indigenous people to Grand Turk and Montserrat, two islands where it is now also extirpated. Our research demonstrates that genetic information spanning paleontological, archaeological, and modern contexts is essential to understand the role of humans in altering the diversity and distribution of biota.

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Long-term land-use change impacts tropical bird communities through population-level and functional diversity effects from habitat loss, degradation and fragmentation, leading to land management and conservation challenges. Assessing the temporal impacts of land-use change on occupancy patterns, population change and functional traits of bird species in tropical areas is limited by the treatment of nondetections as true absences or artefacts of low sampling effort during and throughout years. With this in mind, we developed a novel Bayesian species occupancy framework to account for species absences to evaluate bird community changes in Palenque, Chiapas, Mexico, where there is opportunity for study given exceptional records of change across habitats from rainforest to urban centres. We created a novel dataset of population trends for 244 bird species over the years 1900 to 2020 from published short-term field studies, expert field notes and community science pages. Our results show that open area species had higher population increases than forest specialists over time, represented most evidently by the turnover of rainforest specialists for urban species. Modelled influence of functional traits displayed the importance of main habitat types, body mass and habitat and dietary breadth as factors that associated with bird population trends. On average, species with body masses <6.6 and > 948.4 g showed decreasing trends, while all other species showed increasing or stable trends. Our findings illuminate the value of accounting for species absences from several data sources to discover long-term species population trends and affiliated functional traits whose preservation requires conservation and land management action to protect bird ecosystem services. Primary forest conservation is key to maintaining populations of habitat and dietary specialists, such as small understorey insectivorous and large frugivorous species. Protecting rare natural savanna patches from conversion to cattle pasture is vital to prevent further extirpation of native granivores and to slow colonization by exotic and invasive species.

El cambio a largo plazo en el uso de la tierra impacta a las comunidades de aves tropicales a través de los efectos de la diversidad funcional y a nivel de la población debido a la pérdida, degradación y fragmentación del hábitat, lo que lleva a desafíos de gestión y conservación de la tierra. La evaluación de los impactos temporales del cambio de uso de la tierra en los patrones de ocupación, el cambio de población y los rasgos funcionales de las especies de aves en áreas tropicales enfrenta limitaciones al considerar el tratamiento de las no detecciones como ausencias verdaderas o artefactos de bajo esfuerzo de muestreo durante el año y los años. La evaluación de los impactos temporales del cambio de uso de la tierra en los patrones de ocupación, el cambio de población y las características funcionales de las especies de aves en áreas tropicales está limitada por el tratamiento de las no detecciones como verdaderas ausencias o artefactos de bajo esfuerzo de muestreo durante y a lo largo de los años. Con esto en mente, desarrollamos un marco bayesiano novedoso de ocupación de especies para dar cuenta de las ausencias de especies para evaluar los cambios en la comunidad de aves en Palenque, Chiapas, México, donde existe la oportunidad de estudiar dados los registros excepcionales de cambios en los hábitats, desde la selva tropical hasta los centros urbanos. Creamos un nuevo conjunto de datos de tendencias de población para 244 especies de aves durante los años 1900 a 2020 a partir de estudios de campo a corto plazo publicados, notas de campo de expertos y páginas de ciencia comunitaria. Nuestros resultados muestran que las especies de áreas abiertas tuvieron aumentos de población más altos que los especialistas forestales a lo largo del tiempo, representado más evidentemente por la rotación de especialistas de bosques tropicales por especies urbanas. La influencia modelada de los rasgos funcionales mostró la importancia de los principales tipos de hábitat, la masa corporal y el hábitat y la amplitud de la dieta como factores asociados con las tendencias de la población de aves. En promedio, las especies con masas corporales <6,6 g y >948,4 g mostraron tendencias decrecientes, mientras que todas las demás especies mostraron tendencias crecientes o estables. Nuestros hallazgos iluminan el valor de contabilizar las ausencias de especies de varias fuentes de datos para descubrir tendencias de población de especies a largo plazo y rasgos funcionales afiliados cuya preservación requiere acción de conservación y manejo de la tierra para proteger los servicios ecosistémicos de las aves. La conservación de los bosques primarios es clave para mantener las poblaciones de especialistas en hábitat y dieta, como las especies insectívoras pequeñas del sotobosque y las especies frugívoras grandes. Proteger los raros parches naturales de sabana de la conversión en pastos para ganado es vital para evitar una mayor extirpación de los granívoros nativos y para retrasar la colonización por especies invasoras.

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The jaguarundi (Puma yagouaroundi) is a small felid with a historical range from central Argentina through southern Texas. Information on the current distribution of this reclusive species is needed to inform recovery strategies in the United States where its last record was in 1986 in Texas. From 2003 to 2021, we conducted camera-trap surveys across southern Texas and northern Tamaulipas, México to survey for medium-sized wild cats (i.e., ocelots [Leopardus pardalis], bobcats [Lynx rufus], and jaguarundi). After 350,366 trap nights at 685 camera sites, we did not detect jaguarundis at 16 properties or along 2 highways (1050 km2) in Texas. However, we recorded 126 jaguarundi photographic detections in 15,784 trap nights on 2 properties (125.3 km2) in the northern Sierra of Tamaulipas, Tamaulipas, México. On these properties, latency to detection was 72 trap nights, with a 0.05 probability of detection per day and 0.73 photographic event rate every 100 trap nights. Due to a lack of confirmed class I sightings (e.g., specimen, photograph) in the 18 years of this study, and no other class I observations since 1986 in the United States, we conclude that the jaguarundi is likely extirpated from the United States. Based on survey effort and results from México, we would have expected to detect jaguarundis over the course of the study if still extant in Texas. We recommend that state and federal agencies consider jaguarundis as extirpated from the United States and initiate recovery actions as mandated in the federal jaguarundi recovery plan. These recovery actions include identification of suitable habitat in Texas, identification of robust populations in México, and re-introduction of the jaguarundi to Texas.

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Fungiid corals (Cnidaria: Anthozoa: Scleractinia) occur at isolated locations scattered throughout the eastern tropical Pacific. They can be reef-associated but are often found on sand and rubble substrata distant from reef coral habitat. Cycloseris curvata is known in this region from the southern Gulf of California, through Mexico, Costa Rica, and Panamá, and with the southern-most populations occurring in the Galápagos Islands, Ecuador. During Archipelago-wide surveys (1988-2019), living individuals of Cycloseris curvata were observed at only two locations, Devil's Crown (near Floreana Island) and Xarifa Island (near Española Island). The Devil's Crown population was observed from 1988 to 2017, whereas living individuals in the Xarifa population were observed from 2005 to 2009. In 2012 a death assemblage (dead skeletons) was discovered at Darwin Island, at the northern-most extent of the Archipelago. At Devil's Crown, visual surveys were performed annually or biennially from 1990 to 2012, with two more surveys in 2017 and 2019. The living Cycloseris curvata population consisted of 15 individuals in 1990 that gradually increased to 78 individuals by 1995. Over 200 individuals were observed in 1996, and high numbers persisted through 1998 with 335 individuals. Live tissue surface area per polyp ranged from 0.5 to 95.0cm2. The population decreased to 112 individuals in 1999 (following warming associated with the 1997-98 El Niño), with further declines to 20 in 2009 (following cooling associated with the 2007 La Niña) and a rebound to 91 in 2012. After a 5y break in data collection, only one individual (28.3cm2) was observed in 2017, and in 2019 none were observed. Although undetected living Cycloseris curvata populations may exist, and renewed recruitment provides some hope for population reestablishment, it is possible that this fungiid coral species is now extirpated from the Galápagos Archipelago.

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Habitat loss and fragmentation are major threats to the conservation of nonhuman primates. Given that species differ in their responses to fragmented landscapes, identifying the factors that enable them to cope with altered environments or that cause their extirpation is critical to design conservation management strategies. Howler monkeys (Alouatta spp.) are good models for studying the strategies of tolerant arboreal taxa and how they cope with spatial restriction, because they live in habitats ranging from vast pristine forests to small disturbed fragments and orchards. While some aspects of their ecology and behavior are conserved, others vary in predictable ways in response to habitat shrinking and decreasing resource availability. We argue that the ability of individual howler monkeys to inhabit low-quality environments does not guarantee the long-term persistence of the small populations that live under these conditions. Their local extirpation explains why few forest fragments below a given area threshold are frequently inhabited in landscapes where recolonization and gene flow are compromised by long isolation distances or less permeable matrices. In sum, howlers' ability to cope with habitat restriction at the individual level in the short-term may mask the inevitable fate of isolated populations, thereby compromising the persistence of the species at a regional scale in the long-term if howlers' need for protection in large forests is undervalued.

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The San Felipe Hutia, Mesocapromys sanfelipensis, is one of the most endangered species of rodents in the world, and little is known about its ecology, evolution, and ancient distribution. At present, this hutia has been found only in its type locality, Cayo Juan Garcia, a cay in the southwest Cuban insular platform. Here we report for the first time a well preserved fossil skull referred to this species, collected in Cueva del Indio, Mayabeque province, western Cuba. This specimen shows that the modern population of M. sanfelipensis is a marginal relic of its former distribution, a consequence of climatic, eustatic, and neotectonic changes in the last 8 ka years. Also, we reevaluate the cranial characters and measurements that correspond to M. sanfelipensis and found that two of the eight specimens referred to this species and deposited at the Instituto de Ecologia y Sistematica belong to Mesocapromys auritus. Finally, we include six unpublished photos of specimens of M. sanfelipensis captured in 1970 during two expeditions to Cayo Juan Garcia.

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On low islands or island groups such as the Bahamas, surrounded by shallow oceans, Quaternary glacial-interglacial changes in climate and sea level had major effects on terrestrial plant and animal communities. We examine the paleoecology of two species of songbirds (Passeriformes) recorded as Late Pleistocene fossils on the Bahamian island of Abaco-the Eastern bluebird (Sialia sialis) and Hispaniolan crossbill (Loxia megaplaga). Each species lives today only outside of the Bahamian Archipelago, with S. sialis occurring in North and Central America and L. megaplaga endemic to Hispaniola. Unrecorded in the Holocene fossil record of Abaco, both of these species probably colonized Abaco during the last glacial interval but were eliminated when the island became much smaller, warmer, wetter, and more isolated during the last glacial-interglacial transition from ∼15 to 9 ka. Today's warming temperatures and rising sea levels, although not as great in magnitude as those that took place from ∼15 to 9 ka, are occurring rapidly and may contribute to considerable biotic change on islands by acting in synergy with direct human impacts.

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This note reports Peters ghost faced bat Mormoops megalophylla from the island of Barbuda, northern Lesser Antilles. Our record is based on fossil remains recently discovered in uncatalogued material or misidentified specimens within a late Quaternary assemblage collected at Caves 1 and 2, Two-Foot Bay, Barbuda, over 50 years ago and housed at the Vertebrate Paleontology collection at the University of Florida, Florida, USA. This is an extralimital record for M. megalophylla, which extends its past distribution well into the northern Lesser Antilles, increasing the bat diversity and number of extinct species known from this island during the Quaternary.

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This note reports Peters ghost faced bat Mormoops megalophylla from the island of Barbuda, northern Lesser Antilles. Our record is based on fossil remains recently discovered in uncatalogued material or misidentified specimens within a late Quaternary assemblage collected at Caves 1 and 2, Two-Foot Bay, Barbuda, over 50 years ago and housed at the Vertebrate Paleontology collection at the University of Florida, Florida, USA. This is an extralimital record for M. megalophylla, which extends its past distribution well into the northern Lesser Antilles, increasing the bat diversity and number of extinct species known from this island during the Quaternary. (AU)

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The Mountain Coqui (Eleutherodactylus portoricensis) is a frog endemic to montane rainforests in the Cordillera Central and Luquillo Mountains of Puerto Rico. Classified as endangered by the IUCN Red List and as vulnerable by the Department of Natural and Environmental Resources of Puerto Rico, this species has undergone considerable decline in the Luquillo Mountains. To evaluate the population status of E. portoricensis across its entire range, we conducted ~87 hours of surveys at 18 historical localities and 25 additional localities that we considered suitable for this species. We generated occupancy models to estimate the probability of occurrence at surveyed sites and to identify geographic and climatic factors affecting site occupancy. We also constructed a suitability map to visualize population status in relation to the presence of land cover at elevations where the species has been documented, and determined the dates when populations were last detected at historical localities. Eleutherodactylus portoricensis was detected at 14 of 43 localities, including 10 of 18 historical localities, but it was not detected at any localities west of Aibonito (western Cordillera Central). Occupancy models estimated the probability of occurrence for localities in the western Cordillera Central as zero. Site occupancy was positively associated with montane cloud forest, and negatively associated with the western Cordillera Central, maximum temperature, and precipitation seasonality. The suitability map suggests that declines have occurred despite the presence of suitable habitat. We suggest upgrading the extinction risk of E. portoricensis and potentially developing a captive breeding program for this species.

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El objetivo de este estudio fue determinar  si la lobectomía tiroidea video-asistida, realizada en el modelo canino, reduce el tiempo operatorio, el sangramiento, lesiones de las estructuras nerviosas, y mejora los resultados cosméticos de la cicatriz cervical, en comparación con la lobectomía convencional. Se intervinieron 36 perros adultos mestizos sanos, desparasitados, de ambos sexos, procedentes del bioterio del Instituto de Cirugía Experimental de la Universidad Central de Venezuela. Los animales fueron  asignados al azar simple, a dos grupos de estudio: lobectomía tiroidea convencional (LTC) y lobectomía video - asistida (LTVA), sin insuflación de gas. Los resultados estéticos fueron evaluados por los cirujanos de acuerdo a una escala (excelentes, buenos, regulares y malos), observándose los mejores resultados (P<0,05) en el grupo LTVA (promedio ± DE; 9,2 ± 0,5), que en el grupo LTC (promedio ± DE, 5,8±0,7; P<0,001). En el grupo LTVA  el promedio  de tiempo fue 81±3  min mejor que en el LTC 62±4. El sangramiento fue mayor en el LTC (34±5 mL) que en el LTVA (23±5 mL). No se observaron diferencias significativas en cuanto a la paresia o parálisis de los pliegues vocales, o infección de la herida operatoria.  La lobectomía tiroidea video-asistida es una alternativa válida a la cirugía convencional, resultando en un modelo experimental factible y seguro. Se deberían realizar en Medicina humana estudios comparativos y multicéntricos, para determinar la seguridad y eficacia  de estas técnicas.

A study was conducted to determine if the video-assisted lobectomy performed on a canine model, reduces surgical time, bleeding volume, nerve structures injuries; and improves the cosmetic results of the cervical scar, when compared to conventional lobectomy. Thirty-six adult crossbred dogs of either sex from the animal facility of the Institute of Experimental Surgery, Universidad Central de Venezuela were used. The animals were randomly allocated into two experimental groups: Group A: Eighteen dogs who underwent conventional thyroid lobectomy (CTL); Group B: Eighteen dogs who underwent video-assisted thyroid lobectomy (VATL) without gas insulation. Cosmetic results were assessed by surgeons according to a scale, as follows: excellent, good, average, and bad. The results of the experiment show that dogs operated with the VATL technique exhibited significantly (P<0.05) the highest improvements (9.2±0.5), when compared to the CTL technique (5.8±0.7).  Surgical time lasted longer (P<0.001) in dogs under VATL (81±3 min) than in dogs subjected to CTL (62±4 min). Bleeding volume was significantly higher in CTL (34±5 mL) than in VATL (23±5 mL). No statistically significant differences were found regarding paralysis of vocal cords or surgical wound infections. The VATL is a valid alternative in conventional surgery, becoming a feasible and safe experimental model. Comparative and multicentric studies should be carried out in human subjects to determine both safety and efficacy of these techniques.