| Titre : | Wildlife Research : Management and Conservation 35(4) - 2008 |
| Type de document : | Bulletin |
| Paru le : | 00/00/0000 |
Dépouillements
Article
David Choquenot, Auteur ;
Neil Bolton, Auteur ;
Darrin Woods, Auteur
Himalayan thar (Hemitragus jemlahicus Smith) inhabit a large area of New Zealand's southern alps. Since 1993, a control plan for thar has required estimation of thar density within management units (MUs), and across their range. We evaluated hel[...]
Article
John P. Tracey, Auteur ;
Peter J. S. Fleming, Auteur ;
Gavin J. Melville, Auteur
Density estimates are seldom examined against actual population size, hence the ability of estimators to correct for bias is unknown. Studies that compare techniques are difficult to interpret because of the uncertainty of adherence to their res[...]
Article
Colin Southwell, Auteur ;
Charles G. M. Paxton, Auteur ;
David L. Borchers, Auteur
Knowledge of penguin abundance at regional and circumpolar scales across the Southern Ocean is important for the development of ecosystem models and to estimate prey consumption by penguins to assess potential competition with fisheries' operati[...]
Article
J. M. Kruger, Auteur ;
B. K. Reilly, Auteur ;
I. J. Whyte, Auteur
Aerial surveys have been used in the Kruger National Park, South Africa, to count large ungulates since the late 1970s. After 1998, aerial line-transect sampling using fixed-wing aircraft and Distance analyses replaced the ' total' counting meth[...]
Article
A. R. Pople, Auteur
The appropriate frequency and precision for surveys of wildlife populations represent a trade-off between survey cost and the risk of making suboptimal management decisions because of poor survey data. The commercial harvest of kangaroos is prim[...]
Article
S. C. Cairns, Auteur ;
G. W. Lollback, Auteur ;
N. Payne, Auteur
As part of a kangaroo management program, eastern grey kangaroos (Macropus giganteus) and common wallaroos (M. robustus robustus) are harvested from three kangaroo management zones in north-eastern New South Wales, Australia. To set sustainable [...]
Article
Gavin J. Melville, Auteur ;
John P. Tracey, Auteur ;
Peter J. S. Fleming, Auteur ;
Brian S. Lukins, Auteur
Recent developments in the application of line-transect models to aerial surveys have used double-observer sampling to account for undercounting on the transect line, a crucial step in obtaining correct population estimates. This method is commo[...]
Article
Rachel M. Fewster, Auteur ;
Anthony R. Pople, Auteur
Aerial surveys of kangaroos (Macropus spp.) in Queensland are used to make economically important judgements on the levels of viable commercial harvest. Previous analysis methods for aerial kangaroo surveys have used both mark-recapture methodol[...]
Article
Jeff Laake, Auteur ;
Michelle J. Dawson, Auteur ;
Jim Hone, Auteur
Mark-recapture and line-transect sampling procedures both provide estimators for visibility bias in aerial surveys, and have coexisted in the literature for decades. Mark-recapture estimators of abundance tend to be negatively biased in this con[...]
Article
Jeff Laake, Auteur ;
Richard J. Guenzel, Auteur ;
John L. Bengtson, Auteur ;
Peter Boveng, Auteur ;
Michael Cameron, Auteur ;
M. Bradley Hanson, Auteur
Altitude and flight speed affect detection probability and they typically vary during the course of most aerial surveys. We demonstrate how these sources of variation can be accommodated with covariates in a line-transect analysis using data fro[...]
Article
Rachel M. Fewster, Auteur ;
Colin Southwell, Auteur ;
David L. Borchers, Auteur ;
Stephen T. Buckland, Auteur ;
Anthony R. Pople, Auteur
Line-transect distance sampling is a widely used method for estimating animal density from aerial surveys. Analysis of line-transect distance data usually relies on a requirement that the statistical distribution of distances of animal groups fr[...]
Article
Peter J. S. Fleming, Auteur ;
John P. Tracey, Auteur
Aerial surveys of wildlife involve a noisy platform carrying one or more observers moving over animals in order to quantify their abundance. This simple-sounding system encapsulates limits to human visual acuity and human concentration, visual a[...]
Article
Richard Barker, Auteur
The key difficulty in assessing animal numbers from the air is that not all animals are seen by the observers. Methods for estimating detection probabilities, or accounting for imperfect detection, are reviewed including double surveys, use of s[...]
Article
Jim Hone, Auteur
Bias, precision and accuracy have been studied extensively in wildlife population estimation including aerial surveys. A review of the literature shows that the concepts of bias and precision are used broadly consistently. Aerial survey data fro[...]
Article
Peter J. S. Fleming, Auteur ;
John P. Tracey, Auteur
Article
Michelle J. Dawson, Auteur ;
Cameron Miller, Auteur
Aerial mark-recapture population estimates utilising the natural markings of wild horses to identify individuals was applied in the Bogong High Plains, Alpine National Park, Victoria. A discrete population of wild horses occupying an area of 180[...]
