Climate change and habitat loss pose the greatest contemporary threats to biodiversity, but their impacts on populations largely vary across species. These differential responses could be caused by complex interactions between landscape and climate change and species‐specific sensitivities. Understanding the factors that determine which species are most vulnerable to the synergistic effects of climate change and habitat loss is a high conservation priority. Here, we ask (a) whether and to what extent land cover moderates the impacts of winter weather on population dynamics of wintering birds, and (b) what role species’ physiology might play in modifying their responses to changing weather conditions. To address these questions, we used thousands of observations collected by citizen scientists participating in Project FeederWatch to build dynamic occupancy models for 14 species of wintering birds. Populations of wintering birds were more dynamic, having higher rates of local extinction and colonization, in more forested landscapes during extreme cold—presumably enabling them to better track resources. However, urban areas appeared to provide refuge for some species, as demonstrated by increased local colonization during the harshest winter weather. Lastly, we found that species‐specific differences in thermal tolerances strongly influenced occupancy dynamics such that species that are less cold‐tolerant were more likely to go locally extinct at colder sites and during colder periods throughout winter. Together, our results suggest that species that are less cold‐tolerant and populations occupying less forested landscapes are most vulnerable to extreme winter weather.
Preserving and restoring wildlife in urban areas benefits both urban ecosystems and the well‐being of urban residents. While urban wildlife conservation is a rapidly developing field, the majority of conservation research has been performed in wildland areas. Understanding the applicability of wildland science to urban populations and the relative importance of factors limiting species persistence are of critical importance to identifying prescriptive management strategies for restoring wildlife to urban parks. We evaluated how habitat fragmentation, habitat quality and mortality threats influence species occupancy and persistence in urban parks. We chose California quail Urban parks had a 0.23 ± 0.02 probability of quail occupancy, with greater occupancy in larger parks that were less isolated from potential source populations, had higher shrub cover and had lower impervious cover. Less isolated parks had higher colonization rates, while larger parks had lower extinction rates. These results align with findings across urban ecology showing greater biodiversity in larger and more highly connected habitat patches. A case study highlighted that interventions to increase effective park size and improve connectivity would be most influential for two highly urban focal parks, while changes to internal land cover would have a relatively small impact. Low joint extinction probability in the parks (0.010 ± 0.013) indicated reintroduced populations could persist for some time.
- NSF-PAR ID:
- 10361358
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Applied Ecology
- Volume:
- 59
- Issue:
- 1
- ISSN:
- 0021-8901
- Page Range / eLocation ID:
- p. 199-209
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Societal Impact Statement With more than half of the human population living in cities, urban parks are some of the most significant places for human–nature interactions and their vegetation can provide a range of ecosystem services; however, the vegetation may not always meet the preferences of visitors. By conducting qualitative semi‐structured interviews with visitors at a range of urban park types interspersed throughout a city, we explored vegetation preferences that may be used to improve park planning, design, and maintenance, as well as educate and engage visitors.
Summary Urban parks provide numerous cultural and ecological benefits, but may not always meet diverse visitor preferences. There is a need for additional on‐site research, which has the potential to gauge vegetation preferences in a more authentic and multi‐sensory context. We asked: how does vegetation in urban parks currently meet visitor preferences?
We performed on‐site semi‐structured interviews with visitors at 15 different parks of three general types (i.e., natural‐passive use, recreational‐active use, and multi‐use parks), using a case study of Portland, Oregon, a mid‐sized city in North America with a temperate climate. We transcribed the interviews and coded them for themes and patterns of meaning.
Visitors across demographics groups discussed trees, size, and diversity/variety as some of their favorite aspects of the vegetation. Trees were important for visitors, particularly for their large size/shade, but vegetation preferences tended to vary across park type and slightly more than half of participants suggested changes. Many recreational‐active and multi‐use park visitors desired more flowers, color, grass, middle growth, trees, and food‐bearing plants, as well as improved placement, while visitors to natural‐passive use parks preferred additional invasive/harmful plant removal.
Integrating visitor vegetation preferences into plant selection, layout, and maintenance has the potential to increase ecosystem services of urban parks. The incorporation of colorful, native flowers for visitors can also provide habitat for native species. Visitors across park types also desired to learn more about plants, and so additional interpretive signs/labels and multi‐sensory gardens can help to engage and educate visitors.
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Abstract Megafauna assemblages have declined or disappeared throughout much of the world, and many efforts are underway to restore them. Understanding the trophic ecology of such reassembling systems is necessary for predicting recovery dynamics, guiding management, and testing general theory. Yet, there are few studies of recovering large‐mammal communities, and fewer still that have characterized food‐web structure with high taxonomic resolution.
In Gorongosa National Park, large herbivores have rebounded from near‐extirpation following the Mozambican Civil War (1977–1992). However, contemporary community structure differs radically from the prewar baseline: medium‐sized ungulates now outnumber larger bodied species, and several apex carnivores remain locally extinct.
We used DNA metabarcoding to quantify diet composition of Gorongosa’s 14 most abundant large‐mammal populations. We tested five hypotheses: (i) the most abundant populations exhibit greatest individual‐level dietary variability; (ii) these populations also have the greatest total niche width (dietary diversity); (iii) interspecific niche overlap is high, with the diets of less‐abundant species nested within those of more‐abundant species; (iv) partitioning of forage species is stronger in more structurally heterogeneous habitats; and (v) selectivity for plant taxa converges within guilds and digestive types, but diverges across them.
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