Including ring loss for surivival analyses

[Luc te Marvelde]

The species I study now is colour ringed extensively. Problem is, 2 different rings are used with different qualities. Green rings fall of at a higher rate than white ones (only based on resightings, no rate calculated)

Is there a way to correct for (and calculate) ring loss when calculating survival rates in Program MARK? Is there a build-in function in MARK?

Previous posts in this forum didnt give a clear answer to these questions.

Luc te Marvelde
University of Groningen (RUG)

[gwhite]

Luc:
There is no built-in function to handle ring loss in MARK. To do so, you have to somehow model the ring loss as well as animal loss. With 2 different kinds of rings that are lost at a different rate, you might be able to model the ring loss. Your ability to do so will depend on the kind of data you have, and how well a model of ring loss works. The reward band studies provide examples of using multiple types of bands to obtain an estimate of band loss.
Gary

[ganghis]

Luc-

If you are comfortable with modeling one type of tag as 'permanent,' I have software you could use, at www.cnr.colostate.edu/~pconn/software.html This is based on a recent paper with Bill Kendall and Mike Samuel modeling collar loss in snow geese (last issue of Biometrics).

If not, I'd suggest consulting the following paper:

Fabrizio MC, Nichols JD, Hines JE, et al.
Modeling data from double-tagging experiments to estimate heterogeneous rates of tag shedding in lake trout (Salvelinus namaycush)
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES 56 (8): 1409-1419 AUG 1999

Check the Patuxent software page or contact Jim Hines about getting software associated with this paper.

Cheers, Paul