The age of island-like habitats impacts habitat specialist species richness

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.

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Seed dispersal by dispersing juvenile animals: a source of functional connectivity in fragmented landscapes

Biology Letters ◽

10.1098/rsbl.2019.0264 ◽

2019 ◽

Vol 15 (7) ◽

pp. 20190264 ◽

Cited By ~ 2

Author(s):

Juan P. González-Varo ◽

Sarah Díaz-García ◽

Juan M. Arroyo ◽

Pedro Jordano

Keyword(s):

Seed Dispersal ◽

Fragmented Landscape ◽

Habitat Specialist ◽

Fragmented Landscapes ◽

Plant Dispersal ◽

Link Functions ◽

The Matrix ◽

Specialist Species ◽

Mobile Link ◽

Habitat Specialist Species

Juvenile animals generally disperse from their birthplace to their future breeding territories. In fragmented landscapes, habitat-specialist species must disperse through the anthropogenic matrix where remnant habitats are embedded. Here, we test the hypothesis that dispersing juvenile frugivores leave a footprint in the form of seed deposition through the matrix of fragmented landscapes. We focused on the Sardinian warbler ( Sylvia melanocephala ), a resident frugivorous passerine. We used data from field sampling of bird-dispersed seeds in the forest and matrix of a fragmented landscape, subsequent disperser identification through DNA-barcoding analysis, and data from a national bird-ringing programme. Seed dispersal by Sardinian warblers was confined to the forest most of the year, but warblers contributed a peak of seed-dispersal events in the matrix between July and October, mainly attributable to dispersing juveniles. Our study uniquely connects animal and plant dispersal, demonstrating that juveniles of habitat-specialist frugivores can provide mobile-link functions transiently, but in a seasonally predictable way.

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Balloniscus glaber (Crustacea, Isopoda, Balloniscidae), a habitat specialist species in a disturbed area of Brazil

Iheringia Série Zoologia ◽

10.1590/1678-476620151054430438 ◽

2015 ◽

Vol 105 (4) ◽

pp. 430-438 ◽

Cited By ~ 5

Author(s):

Diego Costa Kenne ◽

Paula Beatriz Araujo

Keyword(s):

Urban Area ◽

Sexual Maturity ◽

Reproductive Period ◽

Human Influence ◽

Habitat Specialist ◽

Human Interference ◽

Disturbed Forest ◽

Specialist Species ◽

Habitat Specialist Species ◽

Favorable Conditions

ABSTRACT Balloniscus glaber Araujo & Zardo, 1995 (Balloniscidae), a Neotropical Oniscidea, has been recorded historically in environments with low or no human interference. In one of these areas, it was determined as aK-strategist. Recently, however, this species was documented in a disturbed forest within urban limits. The present work revealed that the population in the urban area has high density, high number of ovigerous females and mancae in the population, a long reproductive period, and early sexual maturity. These results suggest that modified environments may provide favorable conditions and that the species is not negatively affected by human influence.

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Taxonomy, habitat choice and distribution of Kimunpsocus flavonimbatus (Rostock, 1879) comb. n. (Psocodea: ‘Psocoptera’: Psocidae)

Entomologica Fennica ◽

10.33338/ef.4438 ◽

2011 ◽

Vol 22 (2) ◽

Author(s):

Gergely Várkonyi ◽

Charles Lienhard

Keyword(s):

Conservation Biology ◽

Forest Structure ◽

Habitat Choice ◽

The Other ◽

Habitat Specialist ◽

Specialist Species ◽

Habitat Specialist Species ◽

First Time ◽

Bark Lice ◽

A New Species

The bark lice Psocus flavonimbatus Rostock, 1879 and Ptycta chubsugulensis Günther, 1982 are assigned to the genus Kimunpsocus Yoshizawa, 2009. The male terminalia of K. flavonimbatus are described for the first time and compared to the corresponding structures of the other known species of the genus. Previously only known from the type locality in Estonia and the municipality of Kuhmo in Finland, K. flavonimbatus is now reported from 13 new sites and as a new species for four municipalities in eastern Central Finland. Analyses of an extensive material strongly suggest that K. flavonimbatus is a habitat-specialist species, confining its occurrence to pristine and semi-natural spruce-dominated forests. Nonetheless, its occurrence seems to be sporadic even in the old-growth forests. Forest structure of a subset of occupied and unoccupied sites is described and the conservation biology of K. flavonimbatus discussed.

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Effects of Urbanization on Stream Ecosystems

Effects of Urbanization on Stream Ecosystems ◽

10.47886/9781888569735.ch21 ◽

2005 ◽

Keyword(s):

Species Richness ◽

Fish Species ◽

Endemic Species ◽

Largemouth Bass ◽

Fish Assemblage ◽

Life Histories ◽

Fish Assemblages ◽

Habitat Alterations ◽

Intensity Index ◽

Specialist Species

Abstract.—We examined fish assemblage responses to urban intensity gradients in two contrasting metropolitan areas: Birmingham, Alabama (BIR) and Boston, Massachusetts (BOS). Urbanization was quantified by using an urban intensity index (UII) that included multiple stream buffers and basin land uses, human population density, and road density variables. We evaluated fish assemblage responses by using species richness metrics and detrended correspondence analyses (DCA). Fish species richness metrics included total fish species richness, and percentages of endemic species richness, alien species, and fluvial specialist species. Fish species richness decreased significantly with increasing urbanization in BIR (r = –0.82, P = 0.001) and BOS (r = –0.48, P = 0.008). Percentages of endemic species richness decreased significantly with increasing urbanization only in BIR (r = – 0.71, P = 0.001), whereas percentages of fluvial specialist species decreased significantly with increasing urbanization only in BOS (r = –0.56, P = 0.002). Our DCA results for BIR indicate that highly urbanized fish assemblages are composed primarily of largescale stoneroller Campostoma oligolepis, largemouth bass Micropterus salmoides, and creek chub Semotilus atromaculatus, whereas the highly urbanized fish assemblages in BOS are dominated by yellow perch Perca flavescens, bluegill Lepomis macrochirus, yellow bullhead Ameiurus natalis, largemouth bass, pumpkinseed L. gibbosus, brown bullhead A. nebulosus, and redfin pickerel Esox americanus. Differences in fish assemblage responses to urbanization between the two areas appear to be related to differences in nutrient enrichment, habitat alterations, and invasive species. Because species richness can increase or decrease with increasing urbanization, a general response model is not applicable. Instead, response models based on species’ life histories, behavior, and autecologies offer greater potential for understanding fish assemblage responses to urbanization.

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Forest-type specialization strongly predicts avian responses to tropical agriculture

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.1724 ◽

2019 ◽

Vol 286 (1913) ◽

pp. 20191724

Author(s):

Jacob B. Socolar ◽

David S. Wilcove

Keyword(s):

Forest Type ◽

Soil Nutrient ◽

Predictive Performance ◽

Species Traits ◽

Habitat Associations ◽

Habitat Specialization ◽

Habitat Features ◽

Specialist Species ◽

Habitat Specialist Species ◽

Poor Soil

Species’ traits influence how populations respond to land-use change. However, even in well-characterized groups such as birds, widely studied traits explain only a modest proportion of the variance in response across species. Here, we show that associations with particular forest types strongly predict the sensitivity of forest-dwelling Amazonian birds to agriculture. Incorporating these fine-scale habitat associations into models of population response dramatically improves predictive performance and markedly outperforms the functional traits that commonly appear in similar analyses. Moreover, by identifying habitat features that support assemblages of unusually sensitive habitat-specialist species, our model furnishes straightforward conservation recommendations. In Amazonia, species that specialize on forests along a soil–nutrient gradient (i.e. both rich-soil specialists and poor-soil specialists) are exceptionally sensitive to agriculture, whereas species that specialize on floodplain forests are unusually insensitive. Thus, habitat specialization per se does not predict disturbance sensitivity, but particular habitat associations do. A focus on conserving specific habitats that harbour highly sensitive avifaunas (e.g. poor-soil forest) would protect a critically threatened component of regional biodiversity. We present a conceptual model to explain the divergent responses of habitat specialists in the different habitats, and we suggest that similar patterns and conservation opportunities probably exist for other taxa and regions.

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Age-dependent colonization of urban habitats: a diachronic approach using carabid beetles and spiders

Animal Biology ◽

10.1163/15707563-00002410 ◽

2013 ◽

Vol 63 (3) ◽

pp. 257-269 ◽

Cited By ~ 14

Author(s):

Marion Varet ◽

Françoise Burel ◽

Denis Lafage ◽

Julien Pétillon

Keyword(s):

Urban Areas ◽

Time Lag ◽

Ecosystem Dynamics ◽

Carabid Beetles ◽

Life History Trait ◽

Generalist Species ◽

High Dispersal ◽

Specialist Species ◽

Habitat Generalist ◽

Habitat Specialist Species

Urbanization creates human disturbance that plays an important role in ecosystem dynamics. Most of the time, there is a time lag between disturbance and colonization. Opportunistic species with high dispersal power colonize first, while habitat specialist species with a lower power of dispersal colonize later; the communities change with time after disturbance. We hypothesize that, following the establishment of a new neighbourhood, arthropod communities will change from habitat generalists to specialists, and will be more similar to those of the adjacent countryside. We selected two groups of invertebrates often used as bioindicators, spiders and carabid beetles. The following parameters were estimated: assemblage composition, species richness, activity-density total and per life history trait (broad habitat preference). The field data were collected in 2010 within 3 towns located in France. Neighbourhoods of 10 and 30 years old were pair-matched in these towns and sampled using pitfall traps set randomly in hedgerows (120 traps in total). 2101 adult spiders belonging to 89 species were collected, whereas the 643 captured carabid beetles belonged to 24 species. We found no evidence of any significant change in carabid beetle and spider communities according to neighbourhood age. The assemblages were mainly composed of habitat generalist species. These results suggest that urban areas can be seen to be in continual state of disruption, and colonization of these areas is assumed to be relatively rapid (i.e., less than 10 years in our case study), although incomplete.

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Environmental conditions affecting spiders in grasslands at the lower reach of the River Tisza in Hungary

Entomologica Fennica ◽

10.33338/ef.4241 ◽

2011 ◽

Vol 22 (1) ◽

pp. 29-38 ◽

Cited By ~ 11

Author(s):

Róbert Gallé ◽

Norbert Vesztergom ◽

Tamás Somogyi

Keyword(s):

Species Richness ◽

Species Composition ◽

Structural Diversity ◽

Relative Area ◽

Lower Reach ◽

Forest Species ◽

Spider Species ◽

Specialist Species ◽

Grassland Types ◽

Number Of Plant Species

The aims of the present study were to reveal the differences between grassland types, and to identify the local and landscape parameters that influence the spider assemblages at the reach of the River Tisza. The rarefied number of spider species was negatively correlated with the proportion of forests in a radius of 500 m around each site. A negative correlation was found between the number of grassland specialist species and the proportion of the forests, but the number of forest species increased significantly with the neighboring forest area. The relative area of neighboring forests, the number of plant species and regular flooding played major roles in shaping of the species composition of spiders. The results of the present study emphasize the importance of the effect of habitat landscape properties on spider assemblages. The structural diversity of the landscape may influence species richness and composition of the habitats.

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