Bellbird without a tail

General birdwatching discussion, help with bird identification, and all other things relating to wild birds and birding in NZ that don't fit in one of the other forums.
User avatar
nzsam
Posts: 79
Joined: Wed Oct 13, 2010 4:27 pm
Location: Gore, Southland
Contact:

Bellbird without a tail

Postby nzsam » Sun Nov 05, 2017 9:36 pm

Hi. How usual is it for a male bellbird to have no tail? I have had two contacts near Te Anau who have seen one (possibly the same bird).
I have just added 2 photos - one taken by each person in their separate gardens.
23312988_1492349767481450_830640589_o.jpg
23312988_1492349767481450_830640589_o.jpg (238.08 KiB) Viewed 2877 times
23269718_10214581982166108_608236326_o.jpg
23269718_10214581982166108_608236326_o.jpg (596.86 KiB) Viewed 2877 times
Jim Kirker
Posts: 219
Joined: Wed Jan 04, 2017 8:54 pm

Re: Bellbird without a tail

Postby Jim Kirker » Mon Nov 06, 2017 10:51 am

Hey Glenda, at first I thought it must be a birth defect then did a quick search and found that at least one study showed that "the frequency of birds with tail loss increased strongly with susceptibility to cat predation. Male birds were disproportionately preyed upon, especially if having song posts low in the vegetation, and if having short flight distances when singing. Colonially breeding species were less susceptible to predation than solitary species."
This bird looks more male than female to my eye, which would fit with escaping from a cat. It's feeding and flying between gardens OK and could still be a tailless mutant and possible forerunner of a new subspecies :)
The article is in Chinese Birds 2010 1(2) Causes of interspecific variation in susceptibilty to cat predation on birds. Moller AP, Erritzoe J, Nielsen JT.
Hopefully the attached link will open.
Cheers, Jim
http://www.birdresearch.dk/unilang/Moel ... B_2010.pdf
User avatar
Liam Ballard
Posts: 236
Joined: Mon Oct 03, 2016 7:51 pm
Location: Mt Eden, Auckland
Contact:

Re: Bellbird without a tail

Postby Liam Ballard » Mon Nov 06, 2017 12:12 pm

Wait so just to clarify Jim, do you think this bird is tail-less because of a beneficial mutation (i.e. harder for cats to catch birds with no tail) or that the bird has lost a tail due to an attempted attack by a cat?

Cheers
Liam Ballard
Jim Kirker
Posts: 219
Joined: Wed Jan 04, 2017 8:54 pm

Re: Bellbird without a tail

Postby Jim Kirker » Mon Nov 06, 2017 8:02 pm

I'd favour an attempted attack, probably by a cat, but maybe it was born tailless and if it was it might have a survival advantage, such as the one you mentioned and not needing to eat the protein required to grow the tail and the energy needed to preen it, move it around, keep it steady, fan it etc. It might put a prospective mate off though :(
andrewcrossland
Posts: 2132
Joined: Mon Dec 14, 2009 2:29 pm
Location: Christchurch

Re: Bellbird without a tail

Postby andrewcrossland » Fri Nov 17, 2017 11:03 am

An escape from a cat or a person who caught it do somehow and held it by the tail. Anyone must netting on the area?
User avatar
nzsam
Posts: 79
Joined: Wed Oct 13, 2010 4:27 pm
Location: Gore, Southland
Contact:

Re: Bellbird without a tail

Postby nzsam » Fri Nov 17, 2017 8:53 pm

Actually there was a mist netting workshop held nearby at the Birds NZ conference this year. Both the people who have seen this bird live near to that site.
andrewcrossland
Posts: 2132
Joined: Mon Dec 14, 2009 2:29 pm
Location: Christchurch

Re: Bellbird without a tail

Postby andrewcrossland » Sat Nov 18, 2017 5:11 pm

........so........... anybody pull a bellbird ou of a net and hold its tail instead of irs head and body........?
User avatar
Oscar Thomas
Posts: 932
Joined: Sat Aug 27, 2011 7:15 pm
Location: Dunedin
Contact:

Re: Bellbird without a tail

Postby Oscar Thomas » Sun Nov 19, 2017 8:48 pm

I extracted and banded a bellbird properly so don’t look at me.. released without harm.

Return to “General Birding Discussion”