Join for FREE
It only takes a minute!

Welcome to BirdForum.
BirdForum is the net's largest birding community, dedicated to wild birds and birding, and is absolutely FREE! You are most welcome to register for an account, which allows you to take part in lively discussions in the forum, post your pictures in the gallery and more.

Reply
 
Thread Tools Rate Thread
Old Friday 1st July 2005, 00:55   #1
sclateria
Registered User

 
Join Date: Dec 2004
Location: Alta Floresta, MT
Posts: 268
Black-bellied vs White-bellied Storm-Petrel

Anyone familiar with these species...?

In HBW vol. 1 the authors note that the legs of Black-bellied Storm-Petrel Fregetta tropica extend beyond the tips of the tail in flight. Is this also the case in White-bellied Storm-Petrel Fregetta grallaria, or can this be a feature to distinguish between the two?

Also, the few sources I have at hand referring to these species note that the black central stripe on the belly of F. tropica is variable - does it ever vary to the point of hardly being visible?

Thanks in advance for any help you can provide.

Brad
sclateria is offline  
Reply With Quote
Old Friday 1st July 2005, 18:26   #2
Jane Turner
Registered User
 
Jane Turner's Avatar

 
Join Date: Oct 2003
Location: Hoylake, Merseyside
Posts: 21,712
I have no experience of either. Just in case you haven't got a copy, Harrison suggests that the variation in underpart colouration has been over estimated , though I am guessing HBW is a more recent publicaton. He states also that beyond plumage, the only reliable sturctural disciminator is a combination of tarsus, middle toe and wing length.
__________________

Last Cheshire Caspian Tern (305) last Red Rocks Green-winged Teal (254), last Garden Green-winged Teal (204), last Self-found Great White Egret (293) Home webcam with sound- if its on there will be a message LIVE STREAMING WEBCAM of Sea/Beach
Jane Turner is offline  
Reply With Quote
BF Supporter 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
Click here to Support BirdForum
Old Friday 1st July 2005, 20:10   #3
sclateria
Registered User

 
Join Date: Dec 2004
Location: Alta Floresta, MT
Posts: 268
I don't have that reference Jane, but it was published after HBW vol. 1

The few drawings of the F. tropica i have found show pretty solid amounts of black below. I'll go to the university library on monday and see if they have a copy of Harrison.

Many thanks

Brad
sclateria is offline  
Reply With Quote
Advertisement
Reply


Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Namibia 24th Oct.- 7th Nov.2004 jdbirdman Vacational Trip Reports 6 Tuesday 1st August 2006 19:37
Spanish Tour brianfm Vacational Trip Reports 10 Monday 9th May 2005 10:42
Scotland Trip - May 2004 Jasonbirder Your Birding Day 11 Saturday 24th July 2004 20:51
South African Trip report jdbirdman Vacational Trip Reports 10 Saturday 23rd November 2002 09:24

{googleads}

Fatbirder's Top 1000 Birding Websites

Search the net with ask.com
Help support BirdForum
Ask.com and get

Page generated in 0.16417503 seconds with 12 queries
All times are GMT. The time now is 11:20.