Wednesday, June 3, 2015

Please help us find our missing bittern!

Please help us find our missing bittern! By Emma Willams PhD researcher on bittern 4 June 2015 Last Spring we put transmitters on six male Australasian bitterns at Lake Whatumā, near Waipukurau, Hawkes Bay. When the breeding season finished in January, and the water levels on the lake dropped, all six bitterns left the area. We have been able to re-find five of these birds but the sixth bittern, Tama Tomoana, is still missing! Can you help us find him? We’re asking anyone with access to telemetry gear to check any wetlands, streams, farm ponds, drains and small lakes in their area. We believe he is still in the Hawkes Bay area but in reality he could be anywhere in the country. Recently an Australasian bittern carrying a satellite transmitter in Australia travelled 550 Km, across two state borders, within 11 days!…We don’t know if our bitterns travel the same distances. We’re assuming that Tama could be anywhere! Join the national hunt…and if you find him please contact Emma on 0272462274,

Wednesday, April 29, 2015

Protocols for the inventory and monitoring of populations of the endangered Australasian bittern

Colin DOC Technical Series Latest publication March 2015 38. (Botaurus poiciloptilus) in New Zealand. C. O’Donnell and E. Williams 2015. DOC Technical Series 38. 40 p. (PDF, 4,143K (opens in new window)) Summary: There is an urgent need for conservation managers to undertake inventory and monitoring programmes for the endangered Australasian bittern (Botaurus poiciloptilus; matuku) in New Zealand. Such programmes can be used to determine the distribution and relative abundance of Australasian bitterns nationally; identify significant habitats, sites and populations to enable their protection and implement conservation management; measure the response and effectiveness of management practices; and measure the health of wetlands. This report describes four protocols for the inventory and monitoring of Australasian bitterns, and also provides a guide to choosing the most appropriate method for a particular objective. The protocols build on previous methods that have been developed in other countries, testing and adapting them for New Zealand conditions, and extending them through the use of automatic recording approaches, which allow efficient sampling in remote and inaccessible locations. The protocols represent current ‘best practice’, but further refinements will likely be made in the future.

Sunday, January 18, 2015

Update from the New Zealand bittern research team: This season, as well as monitoring bitterns at key wetlands nationally, the bittern team has been busy calibrating our monitoring methods. Our aim has been to see how the number of bitterns detected with each method compares with the actual number of bitterns present at the site. To do this we’ve needed to capture as many bitterns as possible at one site (Lake Whatumā). Each captured bittern has been marked through the attachment of a radio transmitter. The attachment of these transmitters enables us to re-find and identify marked birds even when they’re hidden in the dense Raupo. Bitterns are difficult to catch due to their cautious nature and the inaccessibility of their natural habitat. A few bitterns have been caught before in New Zealand, but only by firing a net gun onto the bird from a helicopter - something that is very risky for the bird as well as expensive. To avoid having to use these intrusive methods we’ve been trialling some capture methods that have been used on closely related bittern species overseas. This is the first time in New Zealand that Australasian bitterns have been studied intensively like this. As very little is known about bitterns we are hoping that data from this study can also answer questions like: Where do bitterns go after the breeding season? What habitat types are important to bitterns for feeding and breeding? How big are home range sizes? And do bitterns come back to the same sites every year to breed? These are important questions that no one has the answers for yet. Once answered, this knowledge will be used to identify and manage sites that are important for bitterns, helping us to help prevent the extinction of this fascinating Endangered bird. This season our work was partly funded through the Arawai Kakariki Project and a Ducks Unlimited NZ grant.