Please note: The maps below reflect data processed up to August 2011, and will be updated again soon.
A) Site fidelity: we analyzed the spatial proximity
of first, second and sometimes third, molting, wintering and breeding sites for each
individual. We calculated the mean centers of all molting, wintering and breeding
locations using the best fix per PTT transmission cycle, and then calculated the Euclidean (i.e., straight-line)
distance between centers belonging to the same individual; heron referred to as “pairwise
distances”. In the graphs below, the bars illustrate the number of pairwise
distances within distance bins (same for male and female for easy
comparison), with the line representing the cumulative percent.
* Click on any graph to enlarge as a .pdf in this window
Results:- Site fidelity for both males and females was highest to breeding sites,
with 71% of males and 81% of females having pairwise distances within 5km.
- Males showed higher site fidelity to molting
sites, with 67% of males and 45% of females using sites
within 5km of previous/subsequent sites.
- Females showed higher site fidelity
to wintering sites, with 71% using sites within 5km of
previous/subsequent sites, compared to only 29% of males.
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