A rapid survey of herpetofaunal diversity in Nijhum Dwip National Park, Bangladesh

The ecological effects of habitat use by herpetofaunal species vary widely and recognizing relative habitat value will help to improve conservation theory and practice in a particular landscape. To understand how different habitat uses influence diversity in riparian landscapes, we studied reptile and amphibian assemblages across major habitats (agricultural land, forest, human habitation, and waterbodies) in Nijhum Dwip National Park, Bangladesh. A total of 35 herpetofaunal species were found; among them, 17 were directly observed and 18 were reported from a questionnaire survey. Among the observed species, the Asian Common Toad Duttaphrynus melanostictus was the most commonly seen (relative abundance 0.32). We found that forest habitat contained a greater diversity of herpetofauna than other habitats followed by agricultural land, human habitation, and waterbodies. We also found 8 habitat specialist species and 9 generalist species in this study. Our results show that different habitats support different species assemblages in Nijhum Dwip National Park, signifying the importance of diversified habitats for the herpetofaunal population. Understanding this importance is crucial for identifying matrix environments that can complement the forest habitats of sensitive as well as specialist herpetofaunal species.

Host contributions to the force of Borrelia burgdorferi and Babesia microti transmission differ at edges of and within a small habitat patch

In the northeastern United States, the emergence of Lyme disease has been associated, in part, with the increase of small forest patches. Such disturbed habitat is exploited by generalist species, such as white-footed mice, which are considered the host with the greatest reservoir capacity for the agents of Lyme disease ( Borrelia burgdorferi sensu stricto) and human babesiosis ( Babesia microti ). Spatial risk analyses have identified edge habitat as particularly risky. Using a retrotransposon-based quantitative PCR assay for host bloodmeal remnant identification, we directly measured whether the hosts upon which vector ticks fed differed at the edge or within the contiguous small habitat patch. Questing nymphal deer ticks, Ixodes dammini , the northern clade of Ixodes scapularis , were collected from either the edge or within a thicket on Nantucket Island over 3 transmission seasons and tested for evidence of infection as well as bloodmeal hosts. Tick bloodmeal hosts significantly differed by site as well as by year. Mice and deer were identified most often (49.9%), but shrews, rabbits and birds were also common. Ticks from the edge fed on a greater diversity of hosts than those from the thicket. Surprisingly, mice were not strongly associated with either infection at either sampling site (OR<2 for all). Although shrews were not the most common host utilized by ticks, they were highly associated with both infections at both sites (OR= 4.5 and 7.9 B. burgdorferi and 7.9 and 19.0 B. microti , edge and thicket). We conclude that reservoir hosts may differ in their contributions to infecting ticks between edge and contiguous vegetated patches. Importance Habitat fragmentation is thought to be a main factor in the emergence of Lyme disease and other of the deer tick-transmitted infections. The patchwork of forest and edges promotes altered biodiversity, favoring the abundance of generalist rodents such as white footed mice, heretofore considered a key tick and reservoir host in the northeastern U.S. We used tick bloodmeal analyses to directly identify the hosts from which nymphal deer ticks became infected. We demonstrate that there is considerable microfocality in host contributions to the cohort of infected ticks and that shrews, although they fed fewer ticks than mice, disproportionately influenced the force of pathogen transmission in our site. The venue of transmission of certain deer tick-transmitted agents may comprise a habitat scale of 10 meters or fewer and depend on alternative small mammal hosts such as shrews.

Range Shifts of Overwintering Birds Depend on Habitat Type, Snow Conditions and Habitat Specialization

Climatic warming is forcing numerous species to shift their ranges poleward, which has been demonstrated for many taxa across the globe. Yet, the influence of habitat types on within- and among-species variations of distribution shifts has rarely been studied, especially so for the non-breeding season. Here, we investigated habitat specific shift distances of northern range margins and directions of the center of gravity based on a long-term dataset of overwintering birds in Finland. Specifically, we explored influences of habitat type, snow cover depths, species’ climatic niche and habitat specialization on range shifts from 1980’s to 2010’s in 81 bird species. Birds overwintering in farmlands shifted significantly more often northwards than birds of the same species in rural and forest habitats, while the northern range margin shift distances did not significantly differ among the habitat types. Snow cover was negatively associated with the eastward shift direction across all habitats, while we found habitat specific relations to snow cover with northward shift directions and northern range margins shift distances. Species with stronger habitat specializations shifted more strongly towards north as compared to generalist species, whereas the climatic niche of bird species only marginally correlated with range shifts, so that cold-dwelling species shifted longer distances and more clearly eastwards. Our study reveals habitat specific patterns linked to snow conditions for overwintering boreal birds and highlights importance of habitat availability and preference in climate driven range shifts.

Body weight and blood chemistry of wild coatis that feed on discarded human food

ABSTRACT: The coati (Nasua nasua, Linnaeus 1766) is a generalist species, feeding on often-discarded human food in dumpsters around ecological tourism sites. We investigated the body weight and some blood chemistry variables related to the diet of wild coatis from three parks: Parque Municipal das Mangabeiras (PM), Parque Nacional do Caparaó (PNC) e Estação Ecológica Água Limpa (EEAL). We tested the plasma of 53 coatis for high-density lipoprotein (HDL), alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT), cholesterol (Chol), triglycerides (Trig), and alkaline phosphatase (ALP). Male and female adults did not significantly differ on the weight (P > 0.05) and blood chemistry indexes (P > 0.05). The adult coatis of the PM were heavier than the adult coatis of the other two parks. There were significant differences in HDL (P < 0.04), AST (P < 0.001), ALT (P < 0.001), and GGT (P < 0.001) between adults of the three parks. Only ALT and ALP were significantly different (P < 0.05) among the young coatis. The results suggested the coatis of the three parks have different health status. The consumption of discarded human food seems to affect body weight of the PM coatis. The coatis from PNC and EEAL had blood chemistry profiles suggestive of liver disorder. We recommend carrying on environmental education programs to visitors and additional clinical investigations on coatis from these parks.

Herpetofauna of the Maninjau caldera, West Sumatra, Indonesia, with special account to geckos

The field surveys were conducted in the Maninjau Lake region, Sumatera Barat, Indonesia, in February 2020, mainly on the north-eastern slope of the Maninjau caldera at 450–600 m a.s.l. The slopes of the Maninjau caldera are naturally covered by a tropical rainforest that remains quite undisturbed from an altitude of 900 m up to the crater ridge. Natural vegetation of the northern and eastern slopes at altitudes from 450 and 500 to 600 m a.s.l. is replaced by rice plantations or mixed forest gardens. The typical habitat consisted of an evergreen broad-leaved forest on the slopes along a mountain creek and around a waterfall. Herein, we report 11 new species records for the Maninjau caldera; 9 new species records for Agam Regency; 3 new species records for Sumatra and Indonesia and 1 species of Cnemaspis Strauch, 1887 new for science. The morphology of rare and poorly known species of the bent toed gecko, Cyrtodactylus agamensis (Bleeker, 1860) is described for the first time. A high diversity of Cyrtodactylus Gray, 1827 occurs in Indochina and on the Thai-Malay Peninsula (150 species) but only six species in Sumatra. The Malay-Indochinese genus Cnemaspis has a recent spurt of diversity and now reaches eight species in Sumatra and only one species reaches Java. Current gecko diversity in Sumatra comprises 29 species in eight genera. The level of endemism level in geckos is very high and reaches 48%. The herpetofauna of Maninjau Caldera includes 26 amphibian and 46 reptile species. The faunistic core of the West Sumatran herpetofauna consists of Malay-Sundaic, Sumatran endemic, Sunda-Indochinese and widely distributed Oriental elements. The West Sumatran herpetofauna is characterized by the presence of a mutual species with Indochina, Malaysia, east India, Myanmar, the Andaman and Nicobar islands and Sri Lanka, often with disjunction in the huge territory of Indochina; species with continuous distribution from the Indian subcontinent to Papua and Oceania; and generalist species with wide pan-Indopacific distribution.

The Meta-Organism Response of the Environmental Generalist Pocillopora damicornis Exposed to Differential Accumulation of Heat Stress

Coral bleaching events in the marine environment are now occurring globally, and the frequency and severity of these events are increasing. Critically, these events can cause the symbiosis between Symbiodiniaceae and their coral hosts to break down, but how the microbial community within the coral responds to bleaching is still equivocal. We investigated the impact of thermal stress exposure on the meta-organism responses of the generalist scleractinian coral species Pocillopora damicornis. Using mesocosms to recreate warming scenarios previously observed at Heron Island, we show that P. damicornis symbiont densities and photophysiological parameters declined at a similar rate under thermal stress regardless of the length of pre-bleaching thermal stress, defined here as temperatures above the monthly maximum mean (MMM) for Heron Island but below the local bleaching threshold (MMM + 2°C). However, we find that the P. damicornis microbiome remains stable over time regardless of the degree of thermal stress and the accumulation of pre-bleaching thermal stress. Our study therefore suggests that while P. damicornis is physiologically impacted by bleaching temperatures, the microbial community identified through 16S rRNA sequencing remains unchanged at the ASV level throughout bleaching. Understanding the capacity of a generalist species to withstand bleaching events is imperative to characterizing what coral species will exist on coral reefs following disturbances, as it has been suggested that the success of environmental generalist species may simplify community structure and lead to changes in biodiversity following environmental disturbance.

Species-rich but defaunated: the case of medium and large-bodied mammals in a sustainable use protected area in the Amazon

ABSTRACT Neotropical medium and large-bodied mammals are key elements in forest ecosystems, and protected areas are essential for their conservation. In Brazil, sustainable use protected areas (SU-PAs) allow both the conservation of biodiversity and the sustainable use of natural resources, especially in the Amazon region. However, SU-PAs usually suffer both internal and external pressures, and may be subject to variable degrees of defaunation. We sampled mammals using camera traps in two areas with different forest management and human occupation history in the Tapajós National Forest (TNF), in the western Amazon. Overall, we recorded a rich assemblage of medium and large-sized mammals, though both areas differed in species composition. The area with older and more intense human occupation and forest exploitation had more independent records of generalist species, while large species such as Tapirus terrestris and Panthera onca were recorded exclusively in the area with lower human occupation and no forest management. A comparison of our results with similar studies in other Amazonian sites suggests a reduction in the population size of large-bodied mammals, such as Tapirus terrestris and Tayassu pecari, likely in response to increased human activities. Local differences in human occupation within and between protected areas are common in the Amazon, demanding area-specific actions from public authorities to minimize impacts on wildlife caused by human activities. Specifically in TNF, we recommend long-term monitoring of the responses of mammals to human activities, to better subsidize conservation and management actions.

Variation in Plant–Pollinator Network Structure along the Elevational Gradient of the San Francisco Peaks, Arizona

The structural patterns comprising bimodal pollination networks can help characterize plant–pollinator systems and the interactions that influence species distribution and diversity over time and space. We compare network organization of three plant–pollinator communities along the altitudinal gradient of the San Francisco Peaks in northern Arizona. We found that pollination networks become more nested, as well as exhibit lower overall network specialization, with increasing elevation. Greater weight of generalist pollinators at higher elevations of the San Francisco Peaks may result in plant–pollinator communities less vulnerable to future species loss due to changing climate or shifts in species distribution. We uncover the critical, more generalized pollinator species likely responsible for higher nestedness and stability at the higher elevation environment. The generalist species most important for network stability may be of the greatest interest for conservation efforts; preservation of the most important links in plant–pollinator networks may help secure the more specialized pollinators and maintain species redundancy in the face of ecological change, such as changing climate.