Conservation status and biogeography of Australia's terrestrial mammals

2008 ◽  
Vol 56 (6) ◽  
pp. 411 ◽  
Author(s):  
Andrew A. Burbidge ◽  
N. L. McKenzie ◽  
K. E. C. Brennan ◽  
J. C. Z. Woinarski ◽  
C. R. Dickman ◽  
...  
Keyword(s):  
Variation Partitioning ◽  
Conservation Status ◽  
Current Status ◽  
Indigenous Species ◽  
Group Level ◽  
Terrestrial Mammals ◽  
European Settlement ◽  
Temperature And Precipitation ◽  
Extant Species ◽  
Continental Islands

This paper attempts to identify and explain patterns in the biogeography of Australia’s indigenous terrestrial mammals at the time of European settlement (before modern extinctions), and also compares species’ pre-European and current status by region. From subfossil, historical and contemporary sources, we compiled data on the past geographic range and present status of mammals for Australia’s 85 biogeographic regions. Of the 305 indigenous species originally present, 91 have disappeared from at least half of the bioregions in which they occurred before European settlement. Thirty-nine extant species ‘persist’ in less than 25% of their original bioregions; 28 of these are marsupials and 11 are rodents. Twenty-two of the original 305 species are extinct, a further eight became restricted to continental islands, and 100 have become extinct in at least one bioregion. Over the same period, 26 species of exotic mammals established wild populations and now occupy from one to 85 bioregions. When we classified the bioregions in terms of their original species composition, the 3-group level in the dendrogram approximated the Torresian, Eyrean and Bassian subregions proposed by Spencer in 1898, while the 4-group level separated southern semiarid Eyrean bioregions, including those in south-west Australia, from the arid Eyrean bioregions. The classification dendrogram showed geographically (and statistically) discrete clustering down to the 19-group level, suggesting that all four subregions can be further divided on the basis of their mammal faunas. Variation partitioning showed 66% of the biogeographical pattern can be explained by environmental factors (related to temperature and precipitation), the spatial position of each bioregion (a third-order polynomial of latitude and longitude), the area of each bioregion, and the richness of species in each bioregion. In addition to the marked distributional changes that indigenous mammals have experienced over the last 200 years, the 49% of variation explainable by temperature and precipitation implies further shifts with global climate change.

scholarly journals Terrestrial mammal diversity in forests close to pineapple crops, Cutris San Carlos, Costa Rica.

2015 ◽  
Vol 7 (1) ◽  
pp. 59-65
Author(s):  
Jonathan Navarro P ◽  
Alexander Gómez L
Keyword(s):  
Conservation Status ◽  
Forest Fragments ◽  
Negative Effects ◽  
Forest Patches ◽  
Wild Mammals ◽  
Predator Prey ◽  
Terrestrial Mammal ◽  
Terrestrial Mammals ◽  
San Carlos ◽  
Mammal Diversity

Pineapple crops reduce the size of forest fragments and generate pressure on biodiversity in the remnants. To determine potential negative effects of forest fragmentation we assessed diversity and composition of terrestrial mammals in forest patches on three farms under pineapple crops. We placedSherman and Tomahawk traps, footprints traps near water bodies, and made daily tracks to obtain traces and direct observation of mammals. We identified seven species of wild mammals, mostly omnivorous and under a least concern conservation status. The effect of cover type generated by the pineapple crops is consistent with mammal composition. Pineapple crops could enhance the most common wildlife problems, such as predator-prey relationships. Therefore, pineapple plantations, by causing fragmentation and lack of connectivity among forest patches, threaten extinction of mammals in some of their original range.

scholarly journals Current status and conservation of the Endangered Przewalski's gazelle Procapra przewalskii, endemic to the Qinghai–Tibetan Plateau, China

Oryx ◽  
2012 ◽  
Vol 46 (1) ◽  
pp. 145-153 ◽  
Author(s):  
Chunlin Li ◽  
Zhigang Jiang ◽  
Xiaoge Ping ◽  
Jing Cai ◽  
Zhangqiang You ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Population Size ◽  
Conservation Status ◽  
Distance Sampling ◽  
Current Status ◽  
Qinghai Lake ◽  
Conservation Strategies ◽  
Lake Basin ◽  
Domestic Livestock ◽  
Procapra Przewalskii

AbstractIn 2008 Przewalski's gazelle Procapra przewalskii, endemic to the Qinghai–Tibetan Plateau, China, was recategorized from Critically Endangered to Endangered on the IUCN Red List. The species is still, however, threatened, and the human population and accompanying domestic livestock are increasing around Qinghai Lake. Here we provide up-to-date information on the distribution and population size of the species, evaluate its current conservation status and discuss the difficulties of protecting this gazelle species. We used both distance sampling and total counts to survey 16 sites where the species has been reported and found it at 13 of these, occupying a total area of c. 250 km2. Population size estimated from distance sampling (1,635) and total counts (1,544) was similar. About 20% of the gazelles located were in newly discovered areas for the species. The results indicate an overall growth in the population of Przewalski's gazelle since 2003, although some subpopulations have declined or been extirpated. In spite of conservation efforts Przewalski's gazelle is still threatened by habitat degradation and loss, habitat fragmentation, fencing, intensified competition with domestic livestock and predation. Further growth of this gazelle population is constrained by limited habitat availability and human–gazelle conflict. We recommend that management and conservation strategies need to incorporate comprehensive knowledge of the gazelle, long-term monitoring, and captive breeding of injured and orphaned gazelles to form a potential pool of individuals for future reintroductions to the historical range of the species outside the Qinghai Lake basin.

Conservation status of mammals and birds in southwestern Australian forests. I. Is there evidence of direct links between forestry practices and species decline and extinction?

1998 ◽  
Vol 4 (4) ◽  
pp. 296 ◽  
Author(s):  
M. C. Calver ◽  
J. Dell
Keyword(s):  
Negative Impact ◽  
Conservation Status ◽  
Bird Species ◽  
Fire Regimes ◽  
Personal Identification ◽  
Base Line ◽  
Mammal Species ◽  
Current Conservation ◽  
Forestry Practices ◽  
European Settlement

Sixteen mammal species and 22 bird species whose distributions extended into southwestern Australian forests before European settlement have been listed as threatened at some time in Commonwealth legislation, State legislation, or action plans of Environment Australia or its predecessors. Confident assessment of the causes of conservation status is hampered by poor base-line data, few studies of putative impacts and a preponderance of circumstantial or anecdotal rather than experimental evidence. However, introduced foxes were Implicated In the current conservation status of 62% of the mammal species recognized, while 44% of them were negatively impacted by feral cats, 44% by agricultural clearing and 44% by changed fire regimes. Forestry practices were impllcated in the conservation status of only one mammal species. For the bird species recognized, changed fire regimes had the greatest negative impact (45% affected), agricultural clearing affected 41%, draining of wetlands affected 32% and grazing by livestock affected 22%. Forestry practices were not directly implicated in the conservation status of any bird species. While these results suggest that forestry has had minimal direct impact on the mammals and birds of the forests, the conclusion should be treated cautiously because of the poor data. While awaiting a rigorous evaluation, we argue for a strong precautionary approach to forestry in the region. With proper forest management and sound sylvicultural [sic] treatment there is no reason why there should not be built up on the wreckage of the once splendid forests of Western Australia tended forests which will yield for all time 100 cubic feet of timber per acre per year. Lane-Poole (1920). There are many reasons why Australian environmentalists would like to end logging in native forests. The preservation of wilderness, aesthetics, an almost religious identification with old growth forests and the conservation of forest wildlife figure importantly in environmental efforts to restrict logging. Wilderness and a personal identification with trees and undisturbed forests are fundamentally incompatible with logging. Recher (1996).

scholarly journals Using 1st Derivative Reflectance Signatures within a Remote Sensing Framework to Identify Macroalgae in Marine Environments

2019 ◽  
Vol 11 (6) ◽  
pp. 704 ◽  
Author(s):  
Ben Mcilwaine ◽  
Monica Rivas Casado ◽  
Paul Leinster
Keyword(s):  
Early Warning ◽  
Spectral Reflectance ◽  
Nuclear Power ◽  
Detection System ◽  
Agricultural Runoff ◽  
Species Level ◽  
Indigenous Species ◽  
Group Level ◽  
Power Station ◽  
Discrimination Rate

Macroalgae blooms (MABs) are a global natural hazard that are likely to increase in occurrence with climate change and increased agricultural runoff. MABs can cause major issues for indigenous species, fish farms, nuclear power stations, and tourism activities. This project focuses on the impacts of MABs on the operations of a British nuclear power station. However, the outputs and findings are also of relevance to other coastal operators with similar problems. Through the provision of an early-warning detection system for MABs, it should be possible to minimize the damaging effects and possibly avoid them altogether. Current methods based on satellite imagery cannot be used to detect low-density mobile vegetation at various water depths. This work is the first step towards providing a system that can warn a coastal operator 6–8 h prior to a marine ingress event. A fundamental component of such a warning system is the spectral reflectance properties of the problematic macroalgae species. This is necessary to optimize the detection capability for the problematic macroalgae in the marine environment. We measured the reflectance signatures of eight species of macroalgae that we sampled in the vicinity of the power station. Only wavelengths below 900 nm (700 nm for similarity percentage (SIMPER)) were analyzed, building on current methodologies. We then derived 1st derivative spectra of these eight sampled species. A multifaceted univariate and multivariate approach was used to visualize the spectral reflectance, and an analysis of similarities (ANOSIM) provided a species-level discrimination rate of 85% for all possible pairwise comparisons. A SIMPER analysis was used to detect wavebands that consistently contributed to the simultaneous discrimination of all eight sampled macroalgae species to both a group level (535–570 nm), and to a species level (570–590 nm). Sampling locations were confirmed using a fixed-wing unmanned aerial vehicle (UAV), with the collected imagery being used to produce a single orthographic image via standard photogrammetric processes. The waveband found to contribute consistently to group-level discrimination has previously been found to be associated with photosynthetic pigmentation, whereas the species-level discriminatory waveband did not share this association. This suggests that the photosynthetic pigments were not spectrally diverse enough to successfully distinguish all eight species. We suggest that future work should investigate a Charge-Coupled Device (CCD)-based sensor using the wavebands highlighted above. This should facilitate the development of a regional-scale early-warning MAB detection system using UAVs, and help inform optimum sensor filter selection.

Potential competition between two top-order predators following a dramatic contraction in the diversity of their prey base

2011 ◽  
Vol 61 (1) ◽  
pp. 29-47 ◽  
Author(s):  
Raylene Cooke ◽  
Rohan Bilney ◽  
John White
Keyword(s):  
Habitat Management ◽  
Mammalian Species ◽  
Dietary Overlap ◽  
Study Region ◽  
Terrestrial Mammals ◽  
Potential Competition ◽  
European Settlement ◽  
Eastern Australia ◽  
Significant Divergence ◽  
Potential Resource

AbstractTwo sympatric native top-order predators, the sooty owl (Tyto tenebricosa tenebricosa) and powerful owl (Ninox strenua) coexist throughout much of their range in south-eastern Australia. Following European settlement, however, major changes in resource availability for these predators potentially resulted in increased competition, especially for food. This study examined ecological attributes of both species, including intersexual differences in the sooty owl, potential resource partitioning and whether competition may be occurring. Dietary overlap was high between female sooty owls and powerful owls (0.90), compared to overlap between male sooty owls and powerful owls (0.67), with three mammalian species contributing over 74% of their diets. Sooty and powerful owls coexisted throughout the study region, regularly roosting within the same vegetation types, and in similar locations, although microhabitat differences were apparent. Sooty owls displayed aseasonal breeding, although a peak in fledging in spring coincided with powerful owl breeding. Both species exclusively nested in similar size mountain grey gums (Eucalyptus cypellocarpa), however, hollow characteristics differed slightly. Significant divergence along a single niche dimension was not detected between powerful and sooty owls, as they had similar diets, habitat usage and activity times, potentially resulting in competition. Reproductive output was low for both species, however, the degree to which competitive interactions influenced this remains unknown. To minimise potential competition, longterm feral predator control and improved habitat management is recommended to increase the density and diversity of small terrestrial mammals, as this should result in diversification of the sooty owl diet, reducing dietary overlap with powerful owls.

scholarly journals The avifauna and conservation status of the Namuli Massif, northern Mozambique

1999 ◽  
Vol 9 (4) ◽  
pp. 315-331 ◽  
Author(s):  
Peter G. Ryan ◽  
Carlos Bento ◽  
Callan Cohen ◽  
John Graham ◽  
Vincent Parker ◽  
...  
Keyword(s):  
Conservation Status ◽  
Bird Species ◽  
Current Status ◽  
Conservation Action ◽  
Forest Patches ◽  
Commercial Logging ◽  
Remnant Forest ◽  
First Time ◽  
Pristine Forest ◽  
Montane Grasslands

SummaryWe report the current status of birds at the Namuli Massif, northern Mozambique. Despite being the only known locality for the Namuli Apalis Apalis lynesi and the nominate race of the Dapplethroat Arcanator orostruthus, the mountain is very little known ornithologically. Prior to our survey it had only been visited by an ornithologist in 1932, when Jack Vincent collected in the area for three weeks. During our week-long survey in November-December 1998 we recorded 130 bird species from the Namuli area, including all three globally threatened species reported by Vincent (Thyolo Alethe Alethe choloensis, Dapplethroat and Namuli Apalis). The higher-elevation (>1,500 m) forests are still largely intact, but most of those at lower elevations have been cleared for agriculture. The alethe and apalis are common, occurring in remnant forest patches and secondary scrub as well as pristine forest from 1,160 to 2,000 m. The Dapplethroat is restricted to large, intact forests above 1,500 m, but also is fairly common (up to 2–3 singing males per hectare; greater densities than recorded elsewhere). Red-rumped Swallow Hirundo daurica was recorded for the first time in Mozambique, and was suspected of breeding at 1,400 m. We estimate that some 1,300 ha of pristine forest remains on the main massif between Gurue and Mount Namuli, but this area is being reduced by burning and “subsistence” logging. Approximately 7,000 people currently live in the area east of the main forest. Grazing by goats and pigs on the montane grasslands surrounding the forests is another problem, but the gravest threat is posed by improved road access to the area, which could open the forests to commercial logging. In addition to being the sole locality known for the Namuli Apalis and the nominate race of Dapplethroat, the Namuli forests probably support the largest single populations of Thyolo Alethe and the well-marked belcheri race of Green Barbet. These populations make Namuli arguably the most critical Important Bird Area for Mozambique, and the remaining forests have a high priority for conservation action.

scholarly journals Distribution and conservation status of the Antillean manatee (Trichechus manatus manatus) in Honduras

2014 ◽  
Vol 9 (2) ◽  
pp. 123-131
Author(s):  
Daniel Gonzalez-Socoloske ◽  
Cynthia R. Taylor ◽  
Olivia R. Rendon Thompson
Keyword(s):  
Public Awareness ◽  
Conservation Status ◽  
Aerial Survey ◽  
Current Status ◽  
Eastern Coast ◽  
North Coast ◽  
Rapid Population Growth ◽  
Conservation Areas ◽  
Trichechus Manatus ◽  
The North

The Antillean manatee, Trichechus manatus manatus, is among the most threatened mammals in Honduras, yet the last published study is from 1980. Since then, the North Coast of Honduras has experienced rapid population growth and land cover change possibly causing habitat loss for manatees. We conducted aerial, boat, and interview surveys between 2005-2007 along the northern and remote eastern coasts of Honduras to assess the current status and distribution of manatees. In addition, we compiled all available data on manatee mortality from museum specimens, unpublished reports, and interviews to determine current threats. We averaged 1.2 manatee sightings per survey hour during six flights along the North Coast in March-April 2006 during 14.4 aerial survey hours. Sightings were mainly clustered in Cuero y Salado Wildlife Refuge (CSWR) and Rios Chapagua and Aguan, which we indentify as important conservation areas. Our total and average sightings per survey hour in CSWR were much lower than those reported in 1979-80, in spite of the area being protected since 1987. Our interviews indicate that manatees are still present on the eastern coast (La Mosquitia), however we observed none during 14.5 survey hours in June 2005 and April 2007. The major cause of known mortality from 1970-2007, based on 26 records, was due to entanglement in fishnets. Despite local and federal protection, manatees are still poached and opportunistically caught in fishnets. While some efforts have been made by local NGOs to raise public awareness for manatees, a national conservation program is highly recommended to centralize and coordinate efforts.

scholarly journals Temporal stability of an endemic Mexican treefrog

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1274 ◽  
Author(s):  
Griselda Cruz-Ruiz ◽  
Crystian S. Venegas-Barrera ◽  
Hermilo Sanchez-Sanchez ◽  
Javier Manjarrez
Keyword(s):  
Sex Ratio ◽  
Conservation Status ◽  
Temporal Stability ◽  
Current Conservation ◽  
Species Relationship ◽  
Amphibian Population ◽  
Sex Structure ◽  
Temperature And Precipitation ◽  
Precipitation Characteristics ◽  
The Face

The demographic characteristics of an amphibian population fluctuate independently over time, mainly in response to the temporal variation of environmental factors, especially precipitation and temperature. These temporal fluctuations may contribute to the size of an amphibian population and could be used to determine the current conservation status of a species. During a five year (2004–2008) period, we studied the relative abundance, sex ratio, and age-sex structure of a population of metamorphosed individuals of the endemic treefrogHyla eximiain Central Mexico. We also studied the species’ relationship with climatic variables such as temperature and precipitation. We found an interannual constant abundance during the study period. However, interannual differences were observed in the population structure by age-sex category (males, females, or juveniles), with decreased abundance of males and juveniles during the rainy months (August–November). The annual abundance ofH. eximiawas positively correlated with rainfall, but negatively with monthly temperature. We found the sex ratio was male-biased (2:1), except for year 2008. Also, differences in snout-vent length (SVL) were found between years, suggesting changes in recruitment of new individuals. We conclude that variations in abundance, and frequencies by age-sex category, ofH. eximiaare related to seasonal variations in temperature and precipitation characteristics of temperate zones. However, this temporal stability may suggest that anurans have an unusual capacity to persist even in the face of human-induced habitat change.

scholarly journals Temporal stability of an endemic Mexican treefrog

2015 ◽  
Author(s):  
Griselda Cruz-Ruiz ◽  
Crystian S. Venegas-Barrera ◽  
Hermilo Sanchez-Sanchez ◽  
Javier Manjarrez
Keyword(s):  
Sex Ratio ◽  
Conservation Status ◽  
Temporal Stability ◽  
Current Conservation ◽  
Species Relationship ◽  
Amphibian Population ◽  
Temperature And Precipitation ◽  
Precipitation Characteristics ◽  
The Face ◽  
Precipitation And Temperature

The demographic characteristics of an amphibian population fluctuate independently over time, mainly in response to the temporal variation of environmental factors, especially precipitation and temperature. These temporal fluctuations may contribute to the effective size of an amphibian population and could be used to inform the current conservation status of a species. During a five year (2004-2008) period, we studied the relative abundance, sex ratio, and size-age structure of a population of metamorphosed individuals of the endemic treefrog Hyla eximia in Central Mexico. We also studied the species’ relationship with climatic variables such as temperatura and precipitation. We found an interannual constant abundance during the study period. However, interannual differences were observed in the population structure by age-sex category (males, females, or juveniles), with increased abundance of juveniles during the rainy months (August-November). The annual abundance of H. eximia was positively correlated with rainfall, but negatively with monthly temperature. We found the sex ratio was male-biased (2:1) except for year 2008. Also, differences in snout-vent length (SVL) were found between years, suggesting changes in recruitment of new individuals. We conclude that variations in abundance, and frequencies by age-sex category, of H. eximia are related to seasonal variations in temperature and precipitation characteristics of temperate zones. However, this temporal stability may suggest that anurans have an unusual capacity to persist even in the face of human-induced habitat change.

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