This section of the MBO website is intended to be an ever-developing reference guide for banders, as well as others interested in some of the finer points of bird identification.  While we strive to maintain a high standard of accuracy, errors can occur, and there are also some birds which can stimulate considerable debate.  If you believe any photos are mislabeled, please e-mail us with your input. 

This resource is (and always will be) a work in progress, as we continue to learn more about molt patterns and and acquire better photos to illustrate them.  We will add to the library as we band birds of different species and plumages, but also welcome the submission of photos we can use to expand the range of species/ages/sexes covered in this guide.  Note that our intention is to develop a photographic reference that highlights key features useful in determining age and sex, but that for a more thorough treatment of each species, we highly recommend the two-part "Identification Guide to North American Birds" by Peter Pyle (Slate Creek Press, 1997 and 2008), which has formed the basis of much of our knowledge about the ageing and sexing of the species presented here.

The text in the photo library assumes a level of familiarity with terminology used by banders with respect to molt and ageing.  We have started to compile an introduction on some of the frequently used terms and techniques, and welcome any suggestions for additions to it.

How to use this guide:  The MBO Photo Library is designed to help with identifying the age and sex of individuals, generally assuming that species have already been correctly identified.  Any number of popular field guides provide good species-to-species comparisons with an easier overview than is possible with the way we have designed this website.  However, for the warblers and sparrows we have developed some additional tips based on field experience that may be useful complements to other published sources. 

Each species account begins with an "Introductory notes" section* which highlights key points to keep in mind (e.g. similar species, particularly reliable/unreliable plumage features). This is followed by our "Quick tips", which attempt to summarize the best features to use for ageing and sexing of each species.  For many species it is wise to base conclusions on agreement among two or more features.  We have listed tips in decreasing order of priority in terms of typical reliability and ease of assessment, with the hope that this can improve accuracy and reduce handling time by banders.  While most characteristics are easier to assess if the bird is in the hand, many can with practice also be recognized on free-flying birds.
    (* - note that this is a new feature which will gradually be added to species accounts as they are updated in 2011)  

Following the Quick tips section is a table summarizing key attributes by age and sex class, accompanied by representative thumbnail photos of the body, wing, and tail of each combination (as available). The thumbnails each provide a direct link to the corresponding section of the main body of the page below, which includes one or more enlarged photos and accompanying text to further assist in comparisons among age and sex classes.


1) The Migration Research Foundation is pleased to make this resource available free of charge.  However, there are significant costs associated with providing it, ranging from website fees to the considerable expense of operating McGill Bird Observatory, which is the source of a majority of the photos.  If you find the Photo Library useful, please consider making a donation to help us maintain and continue expanding it.  The Migration Research Foundation is a registered charitable organization in both Canada and the United States, and can issue income tax receipts to donors.  Click on the button below to make a donation online through a secure site, or here for information on how to contribute by cheque.

2) All photos and text in the Photo Library are copyright McGill Bird Observatory and may not be reproduced in any manner without prior written consent through contacting us by e-mail

3) We welcome all users to forward this site to friends, or place links to it on your own website, but we ask that you link only to this welcome page, so that all new visitors will have the benefit of the background information above before exploring the species accounts.

Click here to enter the Photo Library

2002- The Migration Research Foundation Inc.