The effect of Noisy Miners on small bush birds: an unofficial cull and its outcome

2008 ◽  
Vol 14 (3) ◽  
pp. 185 ◽  
Author(s):  
S. J. S. Debus

This paper documents the bird community in a small (~15 ha) patch of remnant woodland New South Wales sheep? wheat belt (i) before Noisy Miners Manorina melanocephala were abundant in the patch (1972-79), (ii) after a dense miner colony became established (1980-1990), (iii) after the miners were removed (1991?92) and, subsequently, (iv) while extensive, dense plantings of native trees became established (1992-2006). Bird species richness in the patch was, respectively, 64, 18, 45 and 83 species in each time period. Totals for small (<120 g) bush birds, mostly insectivorous passerines, were 26, 0, 22 and 46 species in the respective time periods. Although this was an unofficial, unreplicated and uncontrolled activity, the results support those of previous similar studies that indicate that Noisy Miners are a major contributor to the local decline of many woodland birds. The results also affirm the value of a shrub layer to small birds.

2006 ◽  
Vol 12 (1) ◽  
pp. 50 ◽  
Author(s):  
S. J. S. Debus ◽  
H. A. Ford ◽  
D. Page

We provide a geographic and landscape context for ongoing studies on bird communities in eucalypt woodland remnants on the New England Tablelands, New South Wales. We draw together several surveys that have not been published in the scientific literature, and integrate them with previously published material. A total of 142 woodland bird species, including 12 threatened species, was recorded in remnant woodland in the area above 900 m elevation from 50 km SSE to 100 km NNW of Armidals. There was a positive relationship between remnant size and bird species richness. Woodland reserves >300 ha supported significantly more species than remnants <100 ha on private land. Intensively surveyed reserves also had more species than remnants surveyed more casually. Threatened and other declining species occurred mainly in medium-sized (100-300 ha) and large reserves; foraging guilds of small to medium-sized, ground and above-ground insectivores were impoverished in degraded medium-sized and small remnants on private land. Almost the full range of woodland bird species was found at one or more sites, indicating their conservation value. However, some species were found in few sites or were only vagrants at a site. Active management will be needed to retain the current diversity of bird species in such heavily cleared landscapes.


2018 ◽  
Vol 10 (7) ◽  
pp. 1136 ◽  
Author(s):  
Sébastien Bonthoux ◽  
Solenne Lefèvre ◽  
Pierre-Alexis Herrault ◽  
David Sheeren

Continuous-based predictors of habitat characteristics derived from satellite imagery are increasingly used in species distribution models (SDM). This is especially the case of Normalized Difference Vegetation Index (NDVI) which provides estimates of vegetation productivity and heterogeneity. However, when NDVI predictors are incorporated into SDM, synchrony between biological observations and image acquisition must be questionned. Due to seasonal variations of NDVI during the year, landscape patterns of habitats are revealed differently from one date to another leading to variations in models’ performance. In this paper, we investigated the influence of acquisition time period of NDVI to explain and predict bird community patterns over France. We examined if the NDVI acquisition period that best fit the bird data depends on the dominant land cover context. We also compared models based on single time period of NDVI with one model built from the Dynamic Habitat Index (DHI) components which summarize variations in vegetation phenology throughout the year from the fraction of radiation absorbed by the canopy (fPAR). Bird species richness was calculated as response variable for 759 plots of 4 km2 from the French Breeding Bird Survey. Bird specialists and generalists to habitat were considered. NDVI and DHI predictors were both derived from MODIS products. For NDVI, five time periods in 2010 were compared, from late winter to begin of autumn. A climate predictor was also used and Generalized Additive Models were fitted to explain and predict bird species richness. Results showed that NDVI-based proxies of dominant habitat identity and spatial heterogeneity explain more bird community patterns than DHI-based proxies of annual productivity and seasonnality. We also found that models’ performance was both time and context-dependent, varying according to the bird groups. In general, best time period of NDVI did not match with the acquisition period of bird data because in case of synchrony, differences in habitats are less pronounced. These findings suggest that the most powerful approach to estimate bird community patterns is the simplest one. It only requires NDVI predictors from a single appropriate time period, in addition to climate, which makes the approach very operational.


2017 ◽  
Vol 23 (4) ◽  
pp. 359 ◽  
Author(s):  
S. J. S. Debus ◽  
W. K. Martin ◽  
J. M. Lemon

Small patches of woodland were progressively established on degraded agricultural land near Gunnedah, northern New South Wales, on the heavily cleared Liverpool Plains. Birds were resurveyed in the plantings, and in agricultural fields (cropping and pasture) and remnant woodland, in 2011–12, 10 years after initial surveys in 2000–01. The plantings in the later survey were 60, 18, 16 and 13 years old, with a shrub layer included in the three youngest cohorts. The survey sites (total 14 ha planted, all within 200 m of remnant woodland) were paired 1-ha plots in each vegetation category. Birds were surveyed by 30-min area searches of each plot eight times over all seasons, using the same plots, procedure and observer as before. In all, 73 species were recorded in the later survey (versus 72 in the earlier survey), for a total of 87 species over both survey periods, with 58 species in 2011–12 (versus 54 in 2000–01) in the plantings; eight of 15 new species visited or colonised the maturing plantings. Avian species richness and abundance increased from the cleared agricultural plots through the progressively older plantings to resemble those in the remnant woodland. Between the first and second surveys, bird communities in the younger plantings converged with those in the older plantings and woodland. The nectar-feeding, foliage-feeding and ground-feeding insectivore guilds benefitted most, having increased in frequency in, or moved into, the younger cohorts of plantings (>13 years old), or both. Several threatened and other declining woodland birds visited, increased in or colonised the plantings. However, noisy miners (Manorina melanocephala) progressively occupied a few plots and excluded some other birds.


2003 ◽  
Vol 9 (2) ◽  
pp. 95 ◽  
Author(s):  
J. A. Seddon ◽  
S. V Briggs ◽  
S. J. Doyle

This study investigated relationships between birds and characteristics of woodland remnants in the central wheat/sheep belt of New South Wales, in order to provide information for conservation management of woodland birds and their habitats in this region. Birds were surveyed in standard area plots in 36 woodland remnants, which ranged from 1 to 1 376 hectares in size, in the central Lachlan catchment in the wheat/sheep belt of New South Wales. Habitat (e.g., shrub cover) and landscape (measures of isolation) characteristics of the remnants were recorded also. Presence/absence occurrences of 20 or more bird species, mostly woodland birds, were positively related to remnant area, shrub cover, number of shrub species, pine cover, fallen logs and branches, and number of remnants within two and five kilometres of the survey remnant. Species of birds that are habitat generalists showed negative or no relationships with these habitat and landscape variables. Richness of all bird species was positively related to remnant area and shrub cover. Number of woodland bird species was positively related to remnant area, shrub cover and tree hollows. Lower species diversities in smaller remnants were most likely caused by lower chances of survival or of successful breeding in small remnants, effects of isolation on the ability of birds to recolonize smaller remnants, small remnants being of insufficient area for some species to form territories, and generally poor habitat quality in small remnants. Retention, management and enhancement of woodland remnants 10 to 20 hectares or larger in size with good understorey cover are necessary for the future viability of woodland birds in the wheat/sheep belt of New South Wales.


1999 ◽  
Vol 5 (3) ◽  
pp. 224 ◽  
Author(s):  
Damon L. Oliver ◽  
Andrew J. Ley ◽  
Hugh A. Ford ◽  
Beth Williams

Five types of woodland and forest in the Bundarra-Barraba region of northern New South Wales were surveyed for Regent Honeyeaters Xanthomyza phrygia and other birds over two years. Regent Honeyeaters were found in 24 of the 93 transects, at a density of 0.09 birds/ha. Most were found in box-ironbark woodland (34% of 62 sites), with single records from box-gum woodland, box-stringybark woodland and dry plateau complex woodland. No Regent Honeyeaters were found in riparian gallery forest during censuses, but they were found breeding there at other times. All habitats contained a high density of birds, compared to other wooded regions in southern Australia, with riparian gallery forest and box-ironbark woodland being particularly rich in species and numbers. These habitats had greater flowering indices, larger trees and more mistletoes than other habitats. Sites used by Regent Honeyeaters supported significantly more birds and bird species than unoccupied sites. The region supports a total of 193 species, four of which are nationally threatened and seven which are threatened in New South Wales. The richness of the bird community in the region is partly because it retains a higher proportion of native vegetation cover (43%) than many other parts of rural Australia. Protection and rehabilitation of box-ironbark woodland and riparian gallery forest is of high priority in a regional conservation plan. However, all habitats in the Bundarra-Barraba region should be protected from clearing and degradation, because they are also used at times by Regent Honeyeaters and support a wide range of bird species. Wise management should retain many sensitive bird species that have disappeared from or declined in other regions of southeastern Australia.


2008 ◽  
Vol 35 (1) ◽  
pp. 19 ◽  
Author(s):  
G. W. Barrett ◽  
D. Freudenberger ◽  
A. Drew ◽  
J. Stol ◽  
A. O. Nicholls ◽  
...  

Tree planting has become a cornerstone strategy for natural resource management in agricultural landscapes, yet its contribution as habitat for woodland birds has not been fully investigated. A case study from the Holbrook region in southern New South Wales was used to assess woodland birds in young plantings of native trees and shrubs. Ground-foraging insectivorous woodland birds were under-represented in the plantings, partly due to a lack of native forb diversity (wildflowers) and leaf litter. Of 69 woodland bird species recorded over a three-year period, 48 species (70%) occurred in planted sites, 59 species (86%) occurred in remnant woodland, and 34 species (49%) occurred in adjacent paddock sites. The greater diversity of birds in planted sites relative to paddock sites was mostly due to understorey birds. The proportion of mist-netted birds recaptured was similar in both planted (15%) and remnant woodland (16%) sites, suggesting that individual birds were staying in planted sites. The proportion of woodland birds showing breeding activity (as measured by the presence of a brood patch) was slightly lower in planted sites (24% of all woodland species) than in remnant woodland (29%). Birds such as the superb fairy-wren, red-browed finch and southern whiteface were more likely to occur in planted sites, suggesting that plantings provide unique, transitional-stage habitat within agricultural landscapes. Restoring native forbs, as part of a broader strategy of woodland management, will help to reverse the decline of ground-foraging insectivorous woodland birds in agricultural landscapes.


1998 ◽  
Vol 76 (2) ◽  
pp. 278-287 ◽  
Author(s):  
J D Matheson ◽  
D W Larson

Cliffs along the Niagara Escarpment in Ontario, Canada, support a long, narrow presettlement forest that includes three distinct geomorphic and vegetation zones: cliff edge, cliff face, and talus slope. This unique landform provides an opportunity to evaluate differences in bird communities between the escarpment and adjacent forest relative to habitat features. We sampled forest birds 12 times during the summer of 1994 in plots located in plateau forests, on talus slope, at cliff edges, and on cliff faces. Eleven habitat variables considered important to birds were also sampled in the plots. We arranged plots along six randomly spaced transects at a south site and a north site. Both sites had the consistent habitat heterogeneity considered important to birds. Bird species richness and composition responded to this heterogeneity, but differently at each site: plateau deciduous forests always had the lowest richness and the simplest species composition, whereas both cliff edges and talus slopes had a higher diversity of birds. Cliff faces had large numbers of species in the south but smaller numbers in the north. Escarpment zones form a habitat mosaic that supports many species not found in the adjacent forest and is consistent with the effect of habitat edge. The results suggest that cliffs represent a significant additive influence on avian biodiversity, even when the cliff is a very narrow component of the landscape.


1992 ◽  
Vol 43 (5) ◽  
pp. 1189 ◽  
Author(s):  
DG Worthington ◽  
DJ Ferrell ◽  
SE NcNeill ◽  
JD Bell

Populations of four species of juvenile fish- Rhabdosargus sarba, Acanthopagrus australis, Achoerodus viridis and Girella tricuspidata-were sampled from a seagrass bed in Botany Bay, New South Wales. Fish were collected eight times between 22 March 1990 and 22 February 1991, using a small seine-net. Growth rates were calculated from the progression of cohorts in length-frequency distributions. Cohorts of R. sarba, A. australis and A. viridis grew most slowly during winter (0.02, 0.04 and 0.21 mm day-1, respectively); growth then increased, peaking just prior to the loss of the cohort from the habitat (0.3 1, 0.24 and 0.39 mm day-1). Populations of R. sarba, A. australis and A. viridis were comprised of one or two cohorts that remained in the habitat for at least 3-4 months. Conversely, up to seven cohorts of G. tricuspidata were found between October and February, and most cohorts did not remain in the habitat for more than 2 months. As a result, there were only two confident estimates of growth for G. tricuspidata: 0.23 mm day-1 between October and November, and 0.34 mm day-1 between January and February. Individuals of each species were also kept in a flow-through 4000-L tank of sea water. Growth of cohorts of fish kept in the tank was very similar to that found in natural populations during the same time period. The rates of recruitment and loss of cohorts from seagrass can be rapid and these factors must be considered in designing a sampling programme to assess growth by analysis of length-frequency distributions.


1981 ◽  
Vol 8 (3) ◽  
pp. 637 ◽  
Author(s):  
RW Howe ◽  
TD Howe ◽  
HA Ford

We studied bird distributions on 15 small patches of subtropical rainforest, ranging from 0.08 to 2.5 ha, in north-eastern New South Wales. Three-quarters of the bird species found in an extensive area of nearby rainforest were recorded in one or more of these isolated patches. Species that were not recorded, generally were rare in the extensive forest or are characterized by large home ranges. Several species more typical of open country were also found in the isolated patches. The number of resident species per patch ranged from one to 19; these were added in a rather predictable order from small to larger areas. Additional species observed in the patches either were transient or had home ranges encompassing several discontinuous areas. Although area is the best single predictor of species richness, isolation, disturbance by livestock and distance from water all tend to reduce the number of resident bird species. We propose that high dispersal abilities of rainforest birds near Dorrigo reflect the geographical and palaeogeographical distribution of Australian rainforest. The small total area and discontinuity of original tracts of rainforest, perhaps accentuated during the Pleistocene, have generally prevented persistence or colonization of highly sedentary, specialized bird species.


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