Species- and sex-specific connectivity effects of habitat fragmentation in a suite of woodland birds

SummaryThe Andean páramo and puna zones may once have been densely dotted by woodlands, mainly ofPolylepis, but human impact has now led to a highly disjunct distribution of this habitat. Because of the habitat fragmentation, many specialized woodland birds now show relictual distributions. Speciations to thePolylepiszone took place in Peru and Bolivia during cold/arid climatic periods, asPolylepis-dominated woodland refuges were isolated away from the humid cis-Andean zone and the pre-Andean scrub-forest in Bolivia. An efficient protection of biodiversity in a minimum of well-managed areas could be achieved, if efforts were concentrated in highlands near the proposed Pleistocene woodland refuges: 55% of all endemic and 67% of all threatened and near-threatened landbirds of the high Andean zone of Peru and Bolivia were recorded within three 10 x 10 km study plots near Cochabamba in Bolivia and east of Abancay and on the east slope of Cordillera Blanca in Peru. The biological basis for the efficiency of this approach is discussed.Los páramos y punas Andinas pueden haber estado densamente poblados de bosques, principalmente dePolylepis, pero el impacto humano ha causado una distribución muy esparcida de este habitat. Debido a la fragmentatión del habitat, muchos pájaros especializados al bosque, ahora muestran distribuciones rudimentales. La diferenciación de las espeties en la zona dePolylepisse dió en Perú y Bolivia durante períodos climáticos fríos/aridos, al igual que los refúgios de bosques dominados porPolylepisfueron aislados de la zona húmeda cis-Andina y de la zone chaqueña en Bolivia. Se podría lograr una protección efitiente de la biodiversidad en un mínimo de áreas bien manejadas, si se concentrasen los esfuerzos en las sierras cerca de los refúgios propuestos de bosque Pleistocenico. Así es, que un 55% de los pájaros endémicos y 67% de todos los especies en peligro de extintión de la zona alto-Andina de Perú y Bolivia fueron registrados dentro de tres áreas de estudio de 10 × 10 km, cerca de Cochabamba en Bolivia, y al sureste de Abancay y en la vertiente oriental de la Cordillera Blanca en Perú. El artículo diserta los processos básicos.

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The effect of recent chaining on birds in the eastern wheatbelt of Western Australia

Pacific Conservation Biology ◽

10.1071/pc060168 ◽

2006 ◽

Vol 12 (3) ◽

pp. 168 ◽

Cited By ~ 4

Author(s):

Graham R. Fulton ◽

Jonathan D. Majer

Keyword(s):

Species Richness ◽

Habitat Fragmentation ◽

Western Australia ◽

Threatened Species ◽

Bird Species ◽

Native Vegetation ◽

Ecological Consequences ◽

Bird Species Richness ◽

Woodland Birds ◽

Near Threatened

The decline of woodland birds that follows from habitat fragmentation, degradation and loss of connectivity is well reported in the literature. However, reports of immediate responses by birds to these events are scant. This study, in the eastern whealtbelt of Western Australia, detected that when half of a 10 ha remnant of Allocasuarina shrubland was chained (vegetation knocked over and largely killed), birds responded quickly; increaser species apparently benefited and decliner species became restricted to the remaining unchained remnant of shrubland. There was some correspondence between the trends in variety and/or abundance of arthropods with those of bird species richness. Two Near-threatened species, the White-browed Babbler Pomatostomus supercilious and the Crested Bellbird Oreoica gutturalis, were only detected in the non-chained part of the remnant. These findings clearly highlight the immediate ecological consequences of clearing of native vegetation, and highlight the importance of conserving even the smallest remaining fragments.

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Effects of habitat fragmentation: increased isolation and reduced habitat size reduces the incidence of dead wood fungi beetles in a fragmented forest landscape

Ecography ◽

10.1034/j.1600-0587.2000.230411.x ◽

2000 ◽

Vol 23 (4) ◽

pp. 492-502 ◽

Cited By ~ 9

Author(s):

Bjorn Arne Rukke

Keyword(s):

Habitat Fragmentation ◽

Dead Wood ◽

Forest Landscape ◽

Habitat Size ◽

Fragmented Forest

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Habitat fragmentation causes collapse of kelp recruitment

Marine Ecology Progress Series ◽

10.3354/meps13422 ◽

2020 ◽

Vol 648 ◽

pp. 111-123

Author(s):

C Layton ◽

MJ Cameron ◽

M Tatsumi ◽

V Shelamoff ◽

JT Wright ◽

...

Keyword(s):

Habitat Fragmentation ◽

Patch Size ◽

Life Stage ◽

Extended Period ◽

Anthropogenic Disturbances ◽

Anthropogenic Sources ◽

Kelp Forests ◽

Natural Disturbances ◽

Short Term ◽

Turf Algae

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.

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Faculty Opinions recommendation of Predictable allele frequency changes due to habitat fragmentation in the Glanville fritillary butterfly.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726165782.793522983 ◽

2016 ◽

Author(s):

Ian Wang

Keyword(s):

Habitat Fragmentation ◽

Allele Frequency ◽

Glanville Fritillary Butterfly ◽

Frequency Changes

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Effects of habitat fragmentation on the use of nest site resources by great tits in Thousand Island Lake,Zhejiang Province

Biodiversity Science ◽

10.3724/sp.j.1003.2010.383 ◽

2010 ◽

Vol 18 (4) ◽

pp. 383 ◽

Cited By ~ 1

Author(s):

Zhang Meng ◽

Sun Jiji ◽

Wang Yanping ◽

Jiang Pingping ◽

Ding Ping ◽

...

Keyword(s):

Habitat Fragmentation ◽

Nest Site ◽

Zhejiang Province

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Landscape heterogeneity buffers biodiversity of simulated meta-food-webs under global change through rescue and drainage effects

Nature Communications ◽

10.1038/s41467-021-24877-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Remo Ryser ◽

Myriam R. Hirt ◽

Johanna Häussler ◽

Dominique Gravel ◽

Ulrich Brose

Keyword(s):

Habitat Fragmentation ◽

Food Web ◽

Food Webs ◽

Landscape Heterogeneity ◽

Landscape Connectivity ◽

Biodiversity Loss ◽

Mechanistic Explanation ◽

Population Densities ◽

Rescue Effect ◽

Drainage Effect

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.

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