How important are different types of temperate woodlands for ground-foraging birds?

2005 ◽  
Vol 32 (6) ◽  
pp. 557 ◽  
Author(s):  
Mark J. Antos ◽  
Andrew F. Bennett
Keyword(s):  
Population Decline ◽  
Bird Species ◽  
Black Box ◽  
Tree Cover ◽  
Suitable Habitat ◽  
Temperate Woodlands ◽  
Declining Species ◽  
Species Richness And Abundance ◽  
River Red Gum ◽  
Cypress Pine

There is widespread concern about population decline in a number of woodland-dependent birds in southern Australia. Of all declining species, approximately half forage on the ground. This study examined the avifaunal assemblages of temperate woodlands of the Northern Plains, Victoria, to investigate the importance of woodland habitats for ground-foraging species. Four main types of woodland were surveyed (white cypress-pine, black box, grey box and river red gum) and, in total, 89 bird species were detected. All four woodland types differed in habitat structure and, in turn, supported significantly different avifaunal assemblages. Forty of the 89 species (45%) foraged, at least in part, on the ground. Species richness and abundance of ground-foragers differed significantly between woodland types, being highest in white cypress-pine and black box. There was a greater richness of ground-foragers during the breeding than non-breeding season, but abundance did not vary seasonally. Overall, ground-foraging birds comprised a greater proportion of species (>55%) and individuals (>60%) in white cypress-pine and black box woodland than in grey box and river red gum (42–48% of species, <50% individuals). Those ground-foragers regarded as declining also occurred in greatest richness in white cypress-pine woodlands, one of the most depleted habitats in the region. The lowest richness of ‘declining’ ground-foraging species was in river red gum woodland, the most widespread woodland type. Throughout Australia, the proportion of ground-foraging species in bird assemblages tends to be greater in temperate, semi-arid or arid woodlands than in moist forests and rainforests. However, in many regions woodland habitats are severely depleted and their open ground layer is particularly vulnerable to degradation. The extent of suitable habitat for ground-foraging birds in temperate woodlands may be much less than is apparent from current measures of tree cover. Sustainable management of drier (non-riverine) temperate woodlands is required to conserve this important element of the Australian avifauna.

MODIS time series as a tool for monitoring fires and their effects on savanna bird diversity

2012 ◽  
Vol 21 (6) ◽  
pp. 680 ◽  
Author(s):  
Noam Levin ◽  
Sarah Legge ◽  
Bronwyn Price ◽  
Michiala Bowen ◽  
Emily Litvack ◽  
...  
Keyword(s):  
Species Richness ◽  
Satellite Imagery ◽  
Bird Species ◽  
Dry Season ◽  
Tree Cover ◽  
Bird Diversity ◽  
Fire Dynamics ◽  
Bird Species Richness ◽  
North West ◽  
Species Richness And Abundance

In this study, we aimed to explore the effect of fires on bird diversity in Australia’s tropical savannas. Bird surveys were conducted at 69 sites between 2005 and 2007 to estimate bird species richness and abundance within the Mornington Sanctuary, the Kimberley, north-west Australia. We used MODIS (Moderate Resolution Imaging Spectroradiometer) and Landsat satellite imagery to map fire scars and to quantify vegetation cover parameters, and QuickBird imagery to map the percentage tree cover. Bird species richness and abundance were higher in areas exhibiting minimum seasonal and interannual changes, e.g. in riparian areas, near water and where tree cover was high. We found a significant negative effect of fire on bird diversity following the extensive late dry-season fires of 2006. These findings support the view that intense and large fires are threatening biodiversity and reinforce the importance of reducing the occurrence of late dry-season fires, which are the most severe and extensive. MODIS satellite imagery was found to provide a cost-effective approach to monitoring savanna landscapes, assessing the state of vegetation and monitoring fire dynamics.

scholarly journals An updated understanding of Texas bumble bee (Hymenoptera: Apidae) species presence and potential distributions in Texas, USA

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3612 ◽  
Author(s):  
Jessica L. Beckham ◽  
Samuel Atkinson
Keyword(s):  
Citizen Science ◽  
Species Distributions ◽  
Field Studies ◽  
The United States ◽  
Bumble Bee ◽  
Suitable Habitat ◽  
Distribution Models ◽  
Species List ◽  
Central Texas ◽  
Declining Species

Texas is the second largest state in the United States of America, and the largest state in the contiguous USA at nearly 700,000 sq. km. Several Texas bumble bee species have shown evidence of declines in portions of their continental ranges, and conservation initiatives targeting these species will be most effective if species distributions are well established. To date, statewide bumble bee distributions for Texas have been inferred primarily from specimen records housed in natural history collections. To improve upon these maps, and help inform conservation decisions, this research aimed to (1) update existing Texas bumble bee presence databases to include recent (2007–2016) data from citizen science repositories and targeted field studies, (2) model statewide species distributions of the most common bumble bee species in Texas using MaxEnt, and (3) identify conservation target areas for the state that are most likely to contain habitat suitable for multiple declining species. The resulting Texas bumble bee database is comprised of 3,580 records, to include previously compiled museum records dating from 1897, recent field survey data, and vetted records from citizen science repositories. These data yielded an updated state species list that includes 11 species, as well as species distribution models (SDMs) for the most common Texas bumble bee species, including two that have shown evidence of range-wide declines: B. fraternus (Smith, 1854) and B. pensylvanicus (DeGeer, 1773). Based on analyses of these models, we have identified conservation priority areas within the Texas Cross Timbers, Texas Blackland Prairies, and East Central Texas Plains ecoregions where suitable habitat for both B. fraternus and B. pensylvanicus are highly likely to co-occur.

scholarly journals Power line routing and configuration as major drivers of collision risk in two bustard species

Oryx ◽  
2020 ◽  
pp. 1-10 ◽  
Author(s):  
Ana Teresa Marques ◽  
Ricardo C. Martins ◽  
João Paulo Silva ◽  
Jorge M. Palmeirim ◽  
Francisco Moreira
Keyword(s):  
Abiotic Factors ◽  
Bird Species ◽  
Power Line ◽  
Power Lines ◽  
Mitigation Measures ◽  
Suitable Habitat ◽  
Collision Risk ◽  
Great Bustard ◽  
Line Configuration ◽  
Tetrax Tetrax

Abstract Collision with power lines is a major cause of mortality for many bird species. Understanding the biotic and abiotic factors that increase collision risk is therefore important for implementing mitigation measures to minimize mortality, such as power line rerouting or wire marking. Here, we used collision events registered during 2003–2015 along 280 km of transmission power lines in southern Portugal to analyse spatio-temporal patterns and collision risk factors in two sympatric, threatened, and collision-prone species: the great bustard Otis tarda and the little bustard Tetrax tetrax. The occurrence of collisions was not uniform across space and time, and variations could be explained by the species' ecological requirements, distribution patterns and behaviour. Although both species fly considerable distances between areas of suitable habitat, collisions were far more likely in power line sections with > 20% (for the little bustard) or > 50% (for the great bustard) of open farmland habitat in the surroundings. Power line configuration was also important: taller pylons and those with a higher number of wire levels posed a higher risk for both species. Wire marking had a small but significant effect for the little bustard, reducing collisions risk. There was, however, no similar effect for the great bustard, possibly a result of limited data. Mitigation measures should be implemented to prevent bustard collisions, including adequate route planning, ideally avoiding areas with > 20% of open habitat. Line configuration and wire marking are particularly important where such localities cannot be avoided and power lines cross areas with a high proportion of bustard habitat, including outside protected areas.

scholarly journals The dynamics underlying avian extinction trajectories forecast a wave of extinctions

2019 ◽  
Vol 15 (12) ◽  
pp. 20190633 ◽  
Author(s):  
Melanie J. Monroe ◽  
Stuart H. M. Butchart ◽  
Arne O. Mooers ◽  
Folmer Bokma
Keyword(s):  
Extinction Risk ◽  
Population Decline ◽  
Bird Species ◽  
Iucn Red List ◽  
Red List ◽  
Extinction Rate ◽  
Critically Endangered Species ◽  
Extinction Rates ◽  
Historical Times ◽  
Risk Categories

Population decline is a process, yet estimates of current extinction rates often consider just the final step of that process by counting numbers of species lost in historical times. This neglects the increased extinction risk that affects a large proportion of species, and consequently underestimates the effective extinction rate. Here, we model observed trajectories through IUCN Red List extinction risk categories for all bird species globally over 28 years, and estimate an overall effective extinction rate of 2.17 × 10 −4 /species/year. This is six times higher than the rate of outright extinction since 1500, as a consequence of the large number of species whose status is deteriorating. We very conservatively estimate that global conservation efforts have reduced the effective extinction rate by 40%, but mostly through preventing critically endangered species from going extinct rather than by preventing species at low risk from moving into higher-risk categories. Our findings suggest that extinction risk in birds is accumulating much more than previously appreciated, but would be even greater without conservation efforts.

Associations of Forest Cover, Fragment Area, and Connectivity with Neotropical Understory Bird Species Richness and Abundance

2012 ◽  
Vol 26 (6) ◽  
pp. 1100-1111 ◽  
Author(s):  
Alexandre Camargo Martensen ◽  
Milton Cezar Ribeiro ◽  
Cristina Banks-Leite ◽  
Paulo Inácio Prado ◽  
Jean Paul Metzger
Keyword(s):  
Species Richness ◽  
Forest Cover ◽  
Bird Species ◽  
Bird Species Richness ◽  
Species Richness And Abundance

Effects of crop diversity on bird species richness and abundance in a highland East African agricultural landscape

Ostrich ◽  
2013 ◽  
Vol 84 (1) ◽  
pp. 33-39 ◽  
Author(s):  
P Kariuki Ndang'ang'a ◽  
John BM Njoroge ◽  
Kamau Ngamau ◽  
Wariara Kariuki ◽  
Philip W Atkinson ◽  
...  
Keyword(s):  
Species Richness ◽  
Agricultural Landscape ◽  
Bird Species ◽  
Crop Diversity ◽  
East African ◽  
Bird Species Richness ◽  
Species Richness And Abundance

Increased grazing and dominance of an exotic pasture (Bothriochloa pertusa) affects vertebrate fauna species composition, abundance and habitat in savanna woodland

2011 ◽  
Vol 33 (1) ◽  
pp. 49 ◽  
Author(s):  
Alex S. Kutt ◽  
Alaric Fisher
Keyword(s):  
Species Composition ◽  
Bird Species ◽  
Information Criteria ◽  
Tree Cover ◽  
Theoretic Approach ◽  
Pasture Grass ◽  
Bird Abundance ◽  
Vertebrate Fauna ◽  
Species Response ◽  
Information Theoretic Approach

The invasion of exotic pasture species into intact woodlands has the potential to affect native fauna by altering habitat structure and ecosystem function. The spread of these weeds is generally in concert with cattle grazing, so that fauna or habitat change is due to multiple interrelated causes. In this study we investigated whether the spread of the introduced pasture grass Bothriochloa pertusa and replacement of the native bluegrass B. ewartiana in eucalypt woodlands of northern Queensland has had an effect on terrestrial vertebrate fauna. We located 40 sites that sampled a range of native and introduced pastures cover, and investigated the spatial pattern of abundance with canonical analysis of principle coordinates, and correlation of the habitat attributes on the ordination space. We then selected a subset of four habitat attributes (eliminating highly colinear variables) and modelled species response to each using an information-theoretic approach. Thirty-one species (26 birds, one mammal and four reptiles) and two summary variables (bird abundance and richness) had best subset Akaike Information Criteria models with reliable parameters estimates. Seventeen models contained the B. pertusa frequency term and a further 16 had a term relating to upper storey cover (tree cover >10, 5–10 or 3–5 m). Though pasture grass cover, grazing and habitat features were correlated and thus we cannot ascribe B. pertusa as the sole determinant of fauna species change, this study has demonstrated that tropical savanna woodlands with changing Bothriochloa dominance from native to introduced species have different fauna species composition. In particular bird species richness, ground nesting species (e.g. rufous songlark Cincloramphus mathewsi, golden-headed cisticola Cisticola exilis) and terrestrial reptiles (e.g. Carlia munda and Ctenotus taeniolatus) declined. Disturbance-tolerant species such as Australian magpie Cracticus tibicen and yellow-throated miners Manorina flavigula increased in abundance in exotic pasture-dominated sites. As pastoral intensification continues in northern Australian rangelands there is a potential for significant change in the relative abundance and composition of vertebrate fauna and the reduction or loss of some species in the landscape.

Defining the key wintering habitats in the Sahel for declining African-Eurasian migrants using expert assessment

2014 ◽  
Vol 24 (4) ◽  
pp. 477-491 ◽  
Author(s):  
PHILIP W. ATKINSON ◽  
WILLIAM M. ADAMS ◽  
JOOST BROUWER ◽  
GRAEME BUCHANAN ◽  
ROBERT A. CHEKE ◽  
...  
Keyword(s):  
Bird Species ◽  
Field Studies ◽  
Habitat Associations ◽  
Expert Assessment ◽  
Rapid Decline ◽  
Breeding Populations ◽  
Western Palearctic ◽  
Wintering Area ◽  
Declining Species ◽  
Migrant Bird

SummaryThe Sahel in West Africa is a major wintering area for many western Palearctic migrants. The breeding populations of many of these have declined over the past 50 years. However, there have been few intensive field studies on migrant ecology in the Sahel and these were generally within a very restricted area. Consequently our knowledge of the distribution of species within this extensive area and the habitat associations of these species is limited. Understanding these habitat associations is essential for the effective conservation management of populations. We brought together a group of experts and consulted a wider group by email to assess the main Sahelian habitat types used by 68 African-Eurasian migrant bird species. Those species that showed strongest declines during 1970–1990 were associated with more open habitats than those newly declining during 1990–2000, when declining species were associated with habitats with more shrubs and trees. Populations of species that winter in the Sahel are generally stable or increasing now as rainfall has increased and is now near the long-term average for the Sahel. Those which use the Sahel only as a staging area are, in many cases, in rapid decline at present.

scholarly journals The effects of using different species conservation priority lists on the evaluation of habitat importance within Hungarian grasslands

2007 ◽  
Vol 17 (1) ◽  
pp. 35-43 ◽  
Author(s):  
PÉTER BATÁRY ◽  
ANDRÁS BÁLDI ◽  
SAROLTA ERDŐS
Keyword(s):  
Conservation Status ◽  
Species Conservation ◽  
Bird Species ◽  
Great Plain ◽  
Conservation Priority ◽  
Threat Status ◽  
Bern Convention ◽  
Conservation Values ◽  
Declining Species ◽  
Eastern European Countries

Many bird species of conservation importance inhabit the grasslands of the Hungarian Great Plain. Although extensive grazing management usually supports more bird species than intensive management, the conservation priority is to protect rare or declining species. Therefore, the conservation status of species must also be included in assessments of the value of different habitats. We used territory mapping to count birds in 21 extensively and intensively grazed field pairs on the Hungarian Great Plain, and subsequently adjusted site scores depending on which species appeared on various lists of priority taxa. We investigated differences in conservation scores of two global conservation lists (the Bonn Convention and another based on values of eight biological characteristics), two West Europe based lists (Bird Directive and CORINE), three continental lists (European Threat Status, SPEC and Bern Convention) and two Hungarian lists (protected species of Hungary and an alternative based on the specifics of Hungarian populations). Extensively managed fields had higher conservation values under seven of the nine priority lists: only the two West Europe based lists showed opposite trends in more than half the study areas. Since both West Europe based lists cover many central and eastern European countries, there is an urgent need to revise these lists, especially the Bird Directive list that gives serious legal responsibilities to countries.

Sign in / Sign up

Export Citation Format

Share Document