CSIRO Publishing Home Books & CDs Journals About Us Shopping Cart
Wildlife Research
  50 years of publishing quality research
You are here: Journals > Wildlife Research   
Search
 
 
  Advanced Search
   
Journal Home
General Information
Scope
Editorial Board
Editorial Contacts
Print Publication Dates
Online Content
For Authors
For Referees
How to Order

 Most Read
Visit our Most Read page regularly to keep up-to-date with the most downloaded papers in this journal.

 Early Alert
Subscribe to our email Early Alert or RSS feeds for the latest journal papers.

 

Distribution and abundance of grebes, pelicans, darters, cormorants, rails and terns in the Alligator Rivers Region, Northern Territory

SR Morton, KG Brennan and MD Armstrong

Abstract

Aerial surveys between 1981 and 1984 were used to identify monthly trends in the abundance of Australian pelicans (Pelecanus conspicillatus), darters (Anhinga melanogaster), little pied cormorants (Phalacrocorax melanoleucos), and whiskered terns (Chlidonias hybrida) on five floodplains of the Alligator Rivers region, 250 km east of Darwin in the monsoonal Northern Territory. Ground surveys were conducted during the same period on one of the floodplains, the Magela plain. The aerial surveys indicated that the Magela floodplain was inhabited by few of these birds during the wet season (November-March), but that numbers then increased substantially in the dry season. The Nourlangie floodplain showed similar patterns, but the numbers of birds tended to be lower. Birds were generally uncommon on the shallower East Alligator and Cooper floodplains. Ground surveys suggested that the birds sought out the persistent swamps that characterise the Magela floodplain in the dry season. Ground surveys also indicated that aerial surveys underestimated densities; on the basis of correction factors calculated from ground surveys, peak numbers on the five floodplains were roughly estimated to be about 2000 darters, 9000 little pied cormorants, 55 000 Australian pelicans and 50 000 whiskered terns. Little black cormorants (Phalacrocorax sulcirostrus) were sometimes abundant, but their sporadic occurrence prevented analysis of seasonal trends. Australasian grebes (Tachybaptus novaehollandiae), great cormorants (Phalacrocorax carbo), pied cormorants (Phalacrocorax varius), buff-banded rails (Rallus philippensis), Baillon's crakes (Porzana pusilla), white-browed crakes (Poliolimnas cinereus), purple swamphens (Porphyrio porphyrio), Eurasian coots (Fulica atra), silver gulls (Larus novaehollandiae), white-winged terns (Chlidonias leucoptera), gull-billed terns (Gelochelidon nilotica) and Caspian terns (Hydroprogne caspia) were recorded in low numbers. The Alligator Rivers region acted as an important dry season refuge because of the unusually persistent fresh waters of the Magela and Nourlangie floodplains and some of the backswamps of the South Alligator, such as Boggy Plain.

Wildlife Research 20(2) 203 - 217 (1993) doi:10.1071/WR9930203

  
Subscriber Login
Username:
Password:  

 View
Issue Contents
PDF (635 KB) $25
Export Citation
Cited by
 Tools
Print
Email this page
    


 
Top  Email this page
 


Legal & Privacy | Sitemap | Contact Us | Help

CSIRO

© CSIRO 1996-2010