Species-specific breeding habitat association of declining farmland birds within urban environments: conservation implications

2021 ◽  
Author(s):  
Jan Havlíček ◽  
Jan Riegert ◽  
Jaroslava Bandhauerová ◽  
Roman Fuchs ◽  
Martin Šálek
2008 ◽  
Vol 84 (4) ◽  
pp. 548-552 ◽  
Author(s):  
Antony W Diamond

Research on forest bird ecology in the ACWERN (Atlantic Cooperative Wildlife Ecology Research Network) lab at the University of New Brunswick, Fredericton, since 1995 has focused on assessing the relative contributions of habitat quality at large (“landscape”) and small (“local” or “stand”) spatial scales. To do so we had to develop methods for assessing key demographic components of fitness (productivity and survival) at large spatial scales. The large extent of forest cover in the Maritimes contrasts with regions where such work has traditionally been carried out, in which forest is clearly fragmented by agriculture or residential development. Our main findings are that spatial effects in highly forested landscapes can often be detected only by using species-specific habitat models, rather than broader categories such as “mature” or “softwood”, that Blackburnian Warblers (Dendroica fusca) are effective indicators of mixedwood forest but define it differently than forest managers do, and that cavity nesters (e.g., woodpeckers) may require different habitat components for nesting and feeding and so cannot be managed for solely on the basis of providing snags for nesting. Our focus has shifted recently to intensive studies on a species at risk, Bicknell's Thrush (Catharus bicknelli), which in New Brunswick breeds in man-made regenerating softwood forest stands, and assessing its response both to precommercial thinning of the breeding habitat and to effects carrying over from the winter habitat in the Caribbean. Key words: landscape effects, thresholds, survival, productivity, fitness, carry-over, habitat, fragmentation


2014 ◽  
Vol 71 (5) ◽  
pp. 763-774 ◽  
Author(s):  
Denis Roy ◽  
David C. Hardie ◽  
Margaret A. Treble ◽  
James D. Reist ◽  
Daniel E. Ruzzante

Assessment of population structure is critical to the design and implementation of sound management and conservation strategies. However, population structure must be assessed using markers attuned to population genetic processes such as genetic drift and gene flow, which reflect actual levels of reproductive isolation among putative genetic clusters. This is critical for highly exploited, commercial species that form the backbone of regional and local economies. Here, we show extremely low levels of population genetic differentiation among Greenland halibut (Reinhardtius hippoglossoides) collected from throughout the Northwest Atlantic, which cannot be statistically differentiated from panmixia using 12 species-specific polymorphic microsatellite markers. In contrast, some previous studies have demonstrated significant differences among individuals collected from various parts of the species’ range using a variety of both genetic and nongenetic techniques. In accordance with other reports and consistent with the species’ life history, we demonstrate that the most parsimonious explanation reconciling observed patterns is a repeated high degree of local differentiation of new recruits and colonizers originating from a common gene pool. Such a scenario has important conservation implications in terms of devising more appropriate strategies balancing species persistence and replenishment with sustainable resource use.


2021 ◽  
Author(s):  
Corey Thomas Callaghan ◽  
Diana Bowler ◽  
Henrique Pereira

Urban expansion poses a serious threat to biodiversity. Given that the expected area of urban land cover is predicted to increase by 2-3 million km2 by 2050, urban environments are one of the most widespread human-dominated land-uses affecting biodiversity. Responses to urbanization differ greatly among species. Some species are unable to tolerate urban environments (i.e., urban avoiders), others are able to adapt and use areas with moderate levels of urbanization (i.e., urban adapters), and yet others are able to colonize and even thrive in urban environments (i.e., urban exploiters). Quantifying species-specific responses to urbanization remains an important goal, but our current understanding of urban tolerance is heavily biased towards traditionally well-studied taxa (e.g., mammals and birds). We integrated a continuous measure of urbanization — VIIRS night-time lights — with over 900,000 species’ observations from GBIF to derive a comprehensive analysis of species-specific (N=158 species) responses of butterflies to urbanization across Europe. The majority of butterfly species included in our analysis avoided urban areas, regardless of whether species’ urban tolerances were quantified as a mean score of urban tolerance across all occurrences (79%) or as a species’ response curve to the whole urbanization gradient (55%). We then used the species-specific responses to urbanization to assess which life history strategies promote urban tolerance in butterflies. These trait-based analyses found strong evidence that the average number of flight months, likely associated with thermal niche breath, and number of adult food types were positively associated with urban tolerance, while hostplant specialism was negatively associated with urban tolerance. Overall, our results demonstrate that specialist butterflies, both in terms of thermal and diet preferences, are most at risk from increasing urbanization, and should thus be considered in urban planning and prioritized for conservation.


2010 ◽  
Vol 5 (2) ◽  
Author(s):  
Laura L. Patton ◽  
David S. Maehr ◽  
Joseph E. Duchamp ◽  
Songlin Fei ◽  
Jonathan W. Gassett ◽  
...  

2011 ◽  
Vol 21 (4) ◽  
pp. 388-393 ◽  
Author(s):  
MATTIA BRAMBILLA ◽  
PAOLO PEDRINI

SummaryAs a double-brooded species inhabiting grassland habitats subject to mowing and located at different elevations, the Corncrake Crex crex in the Alps is potentially affected by changes in its breeding habitat within a season, thus leading to shifts in occurrence and habitat association, with potentially relevant consequences for conservation. We investigated Corncrake abundance in four sites in Trento province (N Italy); two sites were defined as ‘low elevation’ (mean elevation 975 m and 976 m a.s.l., respectively) and two as ‘high elevation’ (mean elevation 1,173 m and 1,177 m). The number of calling males showed a clear variation in relative abundance between early and late periods of the breeding season; in particular, at low elevation sites, abundance decreased from the early to late periods, while the opposite was recorded at high elevation sites. A mixed model suggested that the number of males decreased in the second half of the breeding season and at high elevations, and changed according to mid-season altitudinal shifts. Conservation strategies for this species should take into account the mid-season territory shift.


2012 ◽  
Vol 279 (1736) ◽  
pp. 2135-2141 ◽  
Author(s):  
Deseada Parejo ◽  
Jesús M. Avilés ◽  
Juan Rodríguez

Animals should continuously assess the threat of predation. Alarm calls inform on predation risk and are often used as cues to shape behavioural responses in birds and mammals. Hitherto, however, the ecological consequences of alarm calls in terms of organization of animal communities have been neglected. Here, we show experimentally that calls of a resident nocturnal raptor, the little owl Athene noctua , triggered a response in terms of breeding habitat selection and investment in current reproduction in conspecifics and heterospecifics. Little owls preferred to settle in territories where calls of conspecifics, irrespective of their type (i.e. alarm versus contact calls), were broadcasted, indicating that either conspecific attraction exists or calls are interpreted as foreign calls, eliciting settlement as a mode of defence against competitors. Also, we found that little owls seemed to invest more in current reproduction in safe territories as revealed by conspecific calls. Innovatively, we reported that a second owl species, the migratory scops owl Otus scops , preferred to breed in safe territories as indicated by little owls' calls. These results evidence that the emission of alarm calls may have, apart from well-known behavioural effects, ecological consequences in natural communities by inducing species-specific biases in breeding habitat selection. This study demonstrates a previously unsuspected informative role of avian alarm calls which may modulate the spatial structure of species within communities.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e5999 ◽  
Author(s):  
Caitlin Potter ◽  
Natasha de Vere ◽  
Laura E. Jones ◽  
Col R. Ford ◽  
Matthew J. Hegarty ◽  
...  

Bee populations are currently undergoing severe global declines driven by the interactive effects of a number of factors. Ongoing urbanisation has the potential to exacerbate bee declines, unless steps are taken to ensure appropriate floral resources are available. Sown wildflower strips are one way in which floral resources can be provided to urban bees. However, the use of these strips by pollinators in urban environments remains little studied. Here, we employ pollen metabarcoding of the rbcL gene to compare the foraging patterns of different bee species observed using urban sown wildflower strips in July 2016, with a goal of identifying which plant species are most important for bees. We also demonstrate the use of a non-destructive method of pollen collection. Bees were found to forage on a wide variety of plant genera and families, including a diverse range of plants from outside the wildflower plots, suggesting that foragers visiting sown wildflower strips also utilize other urban habitats. Particular plants within the wildflower strips dominated metabarcoding data, particularly Papaver rhoeas and Phacelia tanacetifolia. Overall, we demonstrate that pollinators observed in sown wildflower strips use certain sown foodplants as part of a larger urban matrix.


1969 ◽  
Vol 26 (8) ◽  
pp. 2061-2077 ◽  
Author(s):  
John E. McInerney

The reproductive biology of the blackspotted stickleback (Gasterosteus wheatlandi) closely parallels that reported elsewhere for G. aculeatus, with certain noteworthy exceptions. Gasterosteus wheatlandi nests in brackish water of low salinity rather than in fresh water. The mature males are gold on the dorsal and lateral surfaces and white on the ventral surface with an irregular series of black spots along the ventro-lateral surfaces of the tail stalk, in contrast to the blue and red highlights of mature colouration in G. aculeatus males. There are marked differences also in the behaviour by which males of the two species lead females to the nest. In the blackspotted stickleback leading consists in an intricate series of movements along the substrate, the male in a head-down position and quivering, the female in a head-up posture with her snout touching the male between his pelvic spines; in contrast, G. aculeatus males simply swim to the nest entrance, the female following with no physical contact. Reproductive isolation between the two species probably depends on breeding habitat separation and female recognition of species-specific male colour patterns. When these fail, incompatible leading behaviours constitute an effective block to interspecific hybridization. Parental fanning in G. wheatlandi resembles that in G. aculeatus except that average bout duration is substantially less. Vertical quivering, a post-spawning activity of unknown function, is unique to G. wheatlandi.


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