conservation.arizona.edu - Population Ecology

Range-wide evolutionary relationships and historical demography of brown bears (Ursus arctos) revealed by whole-genome sequencing of isolated central Asian populations

aburnett93 — Thu, 03 Aug 2023 20:42:14 +0000

Authors

Odbayar Tumendemberel

Sarah Hendricks

Paul Hohenlohe

Jack Sullivan

Andreas Zedrosser

Mona Sæbø

Michael Proctor

John Koprowski

Lisette Waits

Additional Information

Molecular Ecology

Date of publication:

2023

Topics

genomics

connectivity

Research Categories

Population Ecology

Habitat Determinants and Density of the Endemic Sicilian Rock Partridge Alectoris graeca whitakeri on Mt. Etna, Sicily, Italy

aburnett93 — Wed, 13 Jul 2022 23:32:06 +0000

Authors

Stefano Anile

Maria Vittoria Mazzamuto

Mario Lo Valvo

The assessment of the conservation status of a species is the first step to prevent local extinction and to plan appropriate, effective and scientifically sound conservation actions, hence knowledge of the distribution, population trends and characteristics of preferred habitat is crucial for the conservation of a species. Galliformes are facing increasing threats related to overhunting, habitat loss and fragmentation, and human disturbance. The Sicilian Rock Partridge (hereafter Rock Partridge) Alectoris graeca whitakeri is a significant conservation unit endemic to Sicily (Italy) classified as Near Threatened by the IUCN due to a decreasing population. Few studies have been conducted on the occurrence and population density of this subspecies. Here, we estimated its population density and identified which habitat factors drive the occurrence of this species on Mt. Etna. We used a combination of sampling methods (species-specific play-back calls, distance sampling, camera-trapping) to collect count and presence/absence data, which were then integrated into a single habitat model (presence vs. absence). We obtained 24 responses from play-back calls (plus 8 individuals observed while performing the play-back calls), 8 sightings from distance sampling, 6 detections from camera-trapping. Probability of occurrence of Rock Partridge on Mt. Etna was positively driven by shrub and meadow vegetation, whereas its occurrence decreased with an increase in both woody areas (coniferous and deciduous) and elevation. Population density estimated using play-back call data resulted in 0.80 pairs/km² (95% CI: 0.17–2.22) over an area of 53.7 km². The density of Rock Partridge on Mt. Etna appeared to have slightly declined and its distribution undergone a contraction since the previous survey. Several potential threats to the Rock Partridge in Sicily are currently increasing and should be mitigated to ensure the long-term survival of this unique population on Mt. Etna, as well as in the whole island of Sicily.

Additional Information

Acta Ornithologica

Date of publication:

2022

Research Categories

Natural History Population Ecology Spatial Ecology

A Review of Non-Invasive Sampling in Wildlife Disease and Health Research: What’s New?

aburnett93 — Fri, 08 Jul 2022 17:25:04 +0000

Authors

Anna-Katarina Schilling

Maria Vittoria Mazzamuto

Claudia Romeo

The interest in wildlife research has increased in the last decades as more scientists work within a One Health framework that regards human, livestock and wildlife health as connected entities. To minimise the impact of research on wildlife, collecting samples with as little disturbance of the animals as possible is important. In our review, we assess the use of so-called non-invasive sampling and summarise which samples can be used successfully when carrying out research on wildlife diseases and health status. Our results show that interest in minimally invasive sampling has steadily increased since the 2010s. Topics able to employ these methods include disease research, but also stress and other hormone assessments, pollution studies, and dietary studies. At the moment, such methods are mainly used to collect samples from land mammals, however, they can also be used in a wide range of other animals. Ever more capable analytical methods will allow for an even wider use of such “animal-friendly” sampling methods.

Additional Information

Animals

Date of publication:

2022

Topics

Disease ecology

non-invasive methods

Research Categories

Natural History Population Ecology

Timing of resource availability drives divergent social systems and home range dynamics in ecologically similar tree squirrels

mmerrick — Thu, 25 Jun 2020 23:15:21 +0000

Authors

Maria Vittoria Mazzamuto

Melissa Merrick

Francesco Bisi

John Koprowski

Luc Wauters

Adriano Martinoli

Intraspecific variation in home range size has important implications for the distribution of animals across landscapes and the spatial structuring of population, community, and ecosystem processes. Among species of similar trophic guild and body mass, differences in home range size can reflect extrinsic variables that exert divergent selective forces upon spacing behavior and social organization. We tested predictions about how resource availability and timing influence social system, home range size, and territoriality in two tree squirrel species of similar size and ecological niches but that differ in foraging strategy and social organization. We estimated home range size and intraspecific home range core overlap in the Mt. Graham red squirrel (Tamiasciurus fremonti grahamensis; Arizona USA; MGRS) and the Eurasian red squirrel (Sciurus vulgaris; Alps, Italy; ERS) as functions of species, sex, season, and individual’s body mass. However, body mass did not explain differences found between the two species. We found MGRS home ranges being three times smaller with higher core area exclusivity compared to ERS in all seasons. In fact, territorial MGRS evolved in a system of brief resource pulses and are larder hoarders, whereas ERS experience prolonged resource availability and are non-territorial. Only male MGRSs increased their home range during the breeding season, reflecting interspecific differences in social organization and mating behavior. Male ERS home ranges always overlap with several females to enhance mating success although male and female MGRS maintain nearly exclusive territories throughout the year. Only during spring and summer do males temporarily leave their food-based territory to increase mating opportunities with neighboring estrus females. Home range comparisons between ecologically similar species emphasize the importance of divergent extrinsic factors in shaping variability in body size–home range size scaling relationships. Timing in resource availability influenced the social structure and space use in tree squirrels of similar body size, highlighting how the coevolution of arboreal squirrels with conifer tree species has shaped their natural history.

Additional Information

Frontiers in Ecology and Evolution

Date of publication:

2020

Topics

seed predators

home range

Eurasian red squirrel

Mt. Graham red squirrel

forest ecosystems

Research Categories

Natural History Population Ecology Sky Islands Spatial Ecology Threatened and Endangered Species

Phylogeographic and diversification patterns of the white-nosed coati T (Nasua narica): Evidence for south-to-north colonization

thackerk1 — Wed, 24 Jul 2019 00:13:21 +0000

Authors

Sergio F. Nigenda-Morales

Matthew E. Gompper

David Valenzuela

Anna R. Lay

Karen M. Kapheim

Christine Hass

Susan D. Booth-Binczik

Gerald A. Binczik

Ben T. Hirsch

Maureen McColgin

John L. Koprowski

Katherine McFadden

Robert K. Wayne

Klaus-Peter Koepfli

White-nosed coatis (Nasua narica) are widely distributed throughout North, Central, and South America, but the patterns of temporal and spatial diversification that have contributed to this distribution are unknown. In addition, the biogeographic history of procyonid species in the Americas remains contentious. Using sequences from three mitochondrial loci (Cytochrome b, NAHD5 and 16S rRNA; 2201 bp) and genotypes from 11 microsatellite loci, we analyzed genetic diversity to determine phylogeographic patterns, genetic structure, divergence times, and gene flow among Nasua narica populations throughout the majority of the species’ range. We also estimated the ancestral geographic range of N. narica and other procyonid species. We found a high degree of genetic structure and divergence among populations that conform to five evolutionarily significant units. The most southerly distributed population (Panama) branched off much earlier (∼3.8 million years ago) than the northern populations (< 1.2 million years ago). Estimated gene flow among populations was low and mostly northwards and westwards. The phylogeographic patterns within N. narica are associated with geographic barriers and habitat shifts likely caused by Pliocene-Pleistocene climate oscillations. Significantly, our findings suggest the dispersal of N. narica was south-to-north beginning in the Pliocene, not in the opposite direction during the Pleistocene as suggested by the fossil record, and that the most recent common ancestor for coati species was most likely distributed in South or Central America six million years ago. Our study implies the possibility that the diversification of Nasua species, and other extant procyonid lineages, may have occurred in South America.

Additional Information

Molecular Phylogenetics and Evolution

Date of publication:

2018

Topics

Procyonidae

mitochondrial haplotypes

microsatellites

evolutionary history

biogeographical methods White-nosed coatis

Research Categories

Natural History Population Ecology Sky Islands

Altered natal dispersal at the range periphery: the role of behavior, resources, and maternal condition.

thackerk1 — Tue, 23 Jul 2019 23:22:46 +0000

Authors

Melissa J. Merrick

John L. Koprowski

Natal dispersal outcomes are an interplay between environmental conditions and individual phenotypes. Peripheral, isolated populations may experience altered environmental conditions and natal dispersal patterns that differ from populations in contiguous landscapes. We document nonphilopatric, sex-biased natal dispersal in an endangered small mammal, the Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis), restricted to a single mountain. Other North American red squirrel populations are shown to have sex-unbiased, philopatric natal dispersal. We ask what environmental and intrinsic factors may be driving this atypical natal dispersal pat- tern. We test for the influence of proximate factors and ultimate drivers of natal dispersal: habitat fragmentation, local population density, individual behavior traits, inbreeding avoidance, competition for mates, and competition for resources, allow- ing us to better understand altered natal dispersal patterns at the periphery of a species’ range. A juvenile squirrel’s body condition and its mother’s mass in spring (a reflection of her intrinsic quality and territory quality) contribute to individual behavioral tendencies for movement and exploration. Resources, behavior, and body condition have the strongest influence on natal dispersal distance, but affect males and females differently. Male natal dispersal distance is positively influenced by its moth- er’s spring body mass and individual tendency for movement; female natal dispersal distance is negatively influenced by its mother’s spring body mass and positively influenced by individual tendency for movement. An apparent feedback between environmental variables and subsequent juvenile behavioral state contributes to an altered natal dispersal pattern in a peripheral population, highlighting the importance of studying ecological processes at the both range center and periphery of species’ distributions.

Additional Information

Ecology and Evolution

Date of publication:

2016

Topics

Mount Graham Red Squirrel

behavioral phenotype maternal effects

peripheral population

condition-dependent dispersal

phenotype-dependent dispersal

Research Categories

Behavioral Ecology Population Ecology Sky Islands Spatial Ecology Threatened and Endangered Species

Should we consider individual behavior differences in applied wildlife conservation studies?

thackerk1 — Tue, 23 Jul 2019 23:14:47 +0000

Authors

Melissa J. Merrick

John L. Koprowski

Individually distinctive behavioral traits, or personalities, contribute to population-level processes and ecological interactions important in applied wildlife conservation research. Inter-individual variation in behavioral traits (personality) and correlation among behavioral traits (behavioral syndromes), can influence empirical estimates of population size and structure, models of resource selection and population dynamics, harvest and control in wildlife and fisheries populations, population response to disturbance and novel environments, and the success of reintroductions. Despite the important role that personality and behavioral syndromes play in the ecology and dynamics of wildlife populations, a disconnect between basic and applied research realms continues. While the concept of animal personalities and their role in ecology and evolution is increasingly embraced in the animal behavior, ecology, and evolutionary biology literature, it is less represented in applied wildlife management and conservation literature. We identify 10 research foci, often considered the domain of applied wildlife management and conservation, summarize examples of how these research domains may be influenced by personality and behavioral syndromes, and outline potential implications. We suggest that a focus on individuals in wildlife conservation study can bridge the gap between basic and applied research and incorporate knowledge from both realms towards more effective management, conservation, and recovery of populations.

Additional Information

Biological Conservation

Date of publication:

2017

Topics

animal personality

wildlife ecology

conservation

behavioral phenotype

Research Categories

Behavioral Ecology Population Ecology

Dietary niche partitioning among black bears, grizzly bears, and wolves in a multiprey ecosystem

thackerk1 — Tue, 23 Jul 2019 22:56:14 +0000

Authors

Jerod A. Merkle

Jean L. Polfus

Jonathan J. Debridge

Kimberly S. Heinemyer

Identifying mechanisms that promote coexistence of sympatric species is important for predicting ecological effects of anthropogenic change. Many caribou (Rangifer tarandus (L., 1758)) populations are declining, and it is unclear to what extent sympatric predators consume caribou or how alternative prey affect caribou–predator relationships. We used stable isotope mixing models to estimate diets of black bear (Ursus americanus Pallas, 1780), grizzly bear (Ursus arctos L., 1758), and grey wolves (Canis lupus L., 1758) during early, middle, and late summer of 2009–2010 in northwestern British Columbia, Canada. Although we expected wolf diet to be primarily composed of moose (Alces alces (L., 1758)) — as they exist at twice the density of caribou — wolf diet consisted principally of caribou, and to a lesser extent moose and beaver (Castor canadensis Kuhl, 1820), with little change occurring throughout summer. Black bear diet consisted mainly of vegetation and moose, shifting from moose to vegetation through summer. Grizzly bear diet consisted primarily of vegetation and moose, and did not change throughout summer. Our results demonstrate the role of dietary niche partitioning in bear and wolf coexistence, and that caribou may be primary prey for wolves in an ecosystem with relatively high moose abundance and low human development.

Additional Information

Canadian Journal of Zoology

Date of publication:

2017

Topics

black bear

grizzly bear

grey wolf

caribou

predation

niche

diet

trophic relations

stable isotope analysis

Research Categories

Natural History Population Ecology Threatened and Endangered Species

Female-biased sexual size dimorphism: ontogeny, seasonality, and fecundity of the cliff chipmunk (Tamias dorsalis)

thackerk1 — Mon, 22 Jul 2019 21:28:06 +0000

Authors

Allyssa L. Kilanowski

John L. Koprowski

Female-biased sexual dimorphism is uncommon in mammals and is usually attributed to increased fecundity of large females. Moreover, sexual dimorphism is usually described for adults, and the ontogeny of sex differences is poorly documented. We studied cliff chipmunks (Tamias dorsalis), a small mammal with female-biased sexual dimorphism, to describe development of sexual dimorphism in juveniles and to measure sexual dimorphism and seasonal body mass in adults. To test the fecundity hypothesis, we compared body mass of females to litter size and body mass of offspring. Juveniles were not sexually dimorphic at emergence from the nest and did not differ in body mass 2 months after emergence. Adult chipmunks maintained a relatively stable body mass in March–October with females consistently larger than males. Maternal mass did not have an effect on litter size or mass of juveniles. Because females were consistently larger than males, the ontogeny of sexual dimorphism may provide insights into selection pressures that lead to female-biased sexual dimorphism.

Additional Information

Journal of Mammalogy

Date of publication:

2016

Topics

body mass

cliff chipmunk

litter size

small mammal

female-biased sexual dimorphism

Arizona

Research Categories

Natural History Population Ecology Sky Islands

Ecosystem-level effects of keystone species reintroduction: a literature review

thackerk1 — Thu, 27 Jun 2019 23:42:45 +0000

Authors

Sarah L. Hale

John L. Koprowski

The keystone species concept was introduced in 1969 in reference to top‐down regulation of communities by predators, but has expanded to include myriad species at different trophic levels. Keystone species play disproportionately large, important roles in their ecosystems, but human‐wildlife conflicts often drive population declines. Population declines have resulted in the necessity of keystone species reintroduction; however, studies of such reintroductions are rare. We conducted a literature review and found only 30 peer‐reviewed journal articles that assessed reintroduced populations of keystone species, and only 11 of these assessed ecosystem‐level effects following reintroduction. Nine of 11 publications assessing ecosystem‐level effects found evidence of resumption of keystone roles; however, these publications focus on a narrow range of species. We highlight the deficit of peer‐reviewed literature on keystone species reintroductions, and draw attention to the need for assessment of ecosystem‐level effects so that the presence, extent, and rate of ecosystem restoration driven by keystone species can be better understood.

Additional Information

Restoration Ecology

Date of publication:

2018

Topics

ecosystem restoration

keystone species

reintroduction

population declines

ecosystem-level effects

Research Categories

Population Ecology Threatened and Endangered Species