scholarly journals Life on the edge: habitat fragmentation limits expansion of a restored carnivore

2020 ◽  
Author(s):  
A. R. Butler ◽  
K. L. S. Bly ◽  
H. Harris ◽  
R. M. Inman ◽  
A. Moehrenschlager ◽  
...  
2001 ◽  
Vol 79 (11) ◽  
pp. 2063-2071 ◽  
Author(s):  
M Silva

Anthropogenic activities in Prince Edward Island (Canada) have created a mosaic of fragmented uneven-aged forests and agricultural and pasture lands, as well as large amounts of edge habitat. Although the mammalian fauna of the province is largely composed of small mammals, no previous study has investigated how they respond to habitat fragmentation. I surveyed 14 forest fragments in Prince Edward Island National Park to assess the effects of habitat fragmentation on the abundance and diversity of small mammals. A total of 897 small mammals from 11 different species were captured during 10 231 trap-nights. The most frequently captured species were the eastern chipmunk, Tamias striatus (53.5%), and the deer mouse, Peromyscus maniculatus (24.9%). Neither species richness, total population size, nor the Shannon–Wiener species-diversity index (H') was significantly associated with either fragment area or perimeter length. The results also indicated no difference in species diversity between linear fragments and other-shaped fragments. The only species showing a response to edge habitat was the eastern chipmunk. We concluded that future research in Prince Edward Island National Park should assess the abilities of small mammals and their predators to use edge habitats and agricultural fields.


2013 ◽  
pp. 121-135 ◽  
Author(s):  
Stephen F. Ferrari ◽  
Eduardo M. Santos ◽  
Evellyn B. Freitas ◽  
Isadora P. Fontes ◽  
João Pedro Souza-Alves ◽  
...  

2020 ◽  
Vol 648 ◽  
pp. 111-123
Author(s):  
C Layton ◽  
MJ Cameron ◽  
M Tatsumi ◽  
V Shelamoff ◽  
JT Wright ◽  
...  

Kelp forests in many regions are experiencing disturbance from anthropogenic sources such as ocean warming, pollution, and overgrazing. Unlike natural disturbances such as storms, anthropogenic disturbances often manifest as press perturbations that cause persistent alterations to the environment. One consequence is that some kelp forests are becoming increasingly sparse and fragmented. We manipulated patch size of the kelp Ecklonia radiata over 24 mo to simulate persistent habitat fragmentation and assessed how this influenced the demography of macro- and microscopic juvenile kelp within the patches. At the beginning of the experiment, patch formation resulted in short-term increases in E. radiata recruitment in patches <1 m2. However, recruitment collapsed in those same patches over the extended period, with no recruits observed after 15 mo. Experimental transplants of microscopic and macroscopic juvenile sporophytes into the patches failed to identify the life stage impacted by the reductions in patch size, indicating that the effects may be subtle and require extended periods to manifest, and/or that another life stage is responsible. Abiotic measurements within the patches indicated that kelp were less able to engineer the sub-canopy environment in smaller patches. In particular, reduced shading of the sub-canopy in smaller patches was associated with proliferation of sediments and turf algae, which potentially contributed to the collapse of recruitment. We demonstrate the consequences of short- and longer-term degradation of E. radiata habitats and conclude that habitat fragmentation can lead to severe disruptions to kelp demography.


2010 ◽  
Vol 18 (4) ◽  
pp. 383 ◽  
Author(s):  
Zhang Meng ◽  
Sun Jiji ◽  
Wang Yanping ◽  
Jiang Pingping ◽  
Ding Ping ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Remo Ryser ◽  
Myriam R. Hirt ◽  
Johanna Häussler ◽  
Dominique Gravel ◽  
Ulrich Brose

AbstractHabitat fragmentation and eutrophication have strong impacts on biodiversity. Metacommunity research demonstrated that reduction in landscape connectivity may cause biodiversity loss in fragmented landscapes. Food-web research addressed how eutrophication can cause local biodiversity declines. However, there is very limited understanding of their cumulative impacts as they could amplify or cancel each other. Our simulations of meta-food-webs show that dispersal and trophic processes interact through two complementary mechanisms. First, the ‘rescue effect’ maintains local biodiversity by rapid recolonization after a local crash in population densities. Second, the ‘drainage effect’ stabilizes biodiversity by preventing overshooting of population densities on eutrophic patches. In complex food webs on large spatial networks of habitat patches, these effects yield systematically higher biodiversity in heterogeneous than in homogeneous landscapes. Our meta-food-web approach reveals a strong interaction between habitat fragmentation and eutrophication and provides a mechanistic explanation of how landscape heterogeneity promotes biodiversity.


2021 ◽  
Vol 125 ◽  
pp. 107594
Author(s):  
Zhengtao Zhu ◽  
Wenxin Huai ◽  
Zhonghua Yang ◽  
Da Li ◽  
Yisen Wang

2020 ◽  
Vol 23 (3) ◽  
pp. 603-614
Author(s):  
Ikuyo Saeki ◽  
Shigeru Niwa ◽  
Noriyuki Osada ◽  
Wakana Azuma ◽  
Tsutom Hiura

Sign in / Sign up

Export Citation Format

Share Document