Black-billed gull- a local movement

Hi all this bird was sighted next to the Avon River in central Christchurch in March 2010 and was banded almost twelve years prior on the Ashley River- about 30km north. Note birds bill and leg colour- which is highly variable for gulls.
Increasing more information is coming to hand about black-billed gull longevity. Twevle years may not be particularly old for this species.

Blogs function

Hi all -
Please note that this blog site is an informal forum for discussion and commentary about bird banding ( primarily in NZ) and not a repository of banded bird data. All banded bird data should go to the Department of Conservation who manage the national banding office- check out DOC link below for more information. Also some interesting facts about bird banding in New Zealand on this link.

http://www.doc.govt.nz/conservation/native-animals/birds/bird-banding/why-band-birds/

Regards
Peter

I welcome feed back or information for this site.

Contact details -


Peter Langlands
Outdoor/ environmental writing and photography
B.Sc (Zoology) Diploma of Science (Aquatic Ecology)

H: 64 3 338 5373
M: 0274 501 916
E: langlands@xtra.co.nz

P.O.Box 2819
Christchurch Mail Centre
New Zealand

Population and longevity

Hi all- Just found some interesting facts about white-fronted terns on the Birding west coast site.

http://www.birdingwestcoast.co.nz/birding/Birdingdetail/index.cfm/species/71/

The site reports a population estimate of 15-20 000 pairs in 1997. The species is recorded as being in gradual decline, with Northland populations showing a dramatic reported decline.

Longevity record of 26 years reported ( presumably from a banded bird).

Also interesting comments about the sacred element of white-fronted terns , Tara, in Maori culture.

Juvenile white-fronted tern

An increasingly rare sight as terns fail to breed at many coastal sights due to increasing recreational disturbance.

White-fronted tern - metal band sight recovery

With patience white fronted tern band numbers can be read in the field. After 11 years this bird was still alive. Banded by P.Shaw (Wildlife service). Certainly having colour bands- flags would help. While terns have short tarsus, in the right circumstances band numbers can be read in the field with binoculars.

Need for more research on white-fronted terns

There is strong evidence that our white-fronted terns populations are in decline. Certainly in Canterbury I looked through some very large white-fronted terns flocks in January at the base of Kaitorete Spit. In one flock out of 750 birds I noted only two juveniles. Certainly overall the percentage of juveniles sighted was less than 5% out of over 3000 birds observed at various roosting locations in Canterbury in January. I think that recording the % of juvenile birds in white-fronted tern flocks in January, before juveniles disperse, (and possibly segregate from adults) would be an important tool to monitor nationally white fronted tern breeding success. Banding data to date suggests that White-fronted terns are long lived birds and this may be the factor keeping our white fronted terns population going. But is there sufficient recruitment for population viability ? I think we need to have more terns marked nationally to gain more in sight, especially regarding the bird's population age structure.

Banded bird blog

Hello my name is Peter Langlands. I have had a life long interest in ornithology. For me one of the most exciting aspects of bird research is that which comes from banding birds, especially with colour bands, so that birds can be identified in the field. The movements and longevity of individual birds can be monitored. In this informal blog I hope to share some insights that band recoveries I, and others, have made give into the lives of our birds. For conservation research bird banding is an important tool.