Piping Plover - U.S. Fish and Wildlife Service

Currently available genetic information does not provide evidence that Great Lakes and
Northern Great Plains piping plovers are genetically discrete. As outlined above, however, it
is important to consider other potential evidence that Great Lakes and Northern Great Plains
piping plovers may be “markedly separated”, therefore meeting the discreteness criterion of
the DPS policy.
Breeding fidelity and dispersal evidence from banding studies – Banding and monitoring
studies are useful methods for evaluating the discreteness of two populations, provided that
the banding effort adequately samples each population and that the monitoring effort is
sufficient to provide reasonable probabilities of detecting banded individuals. Between 1982
and 2007, 530 Great Lakes and 5,420 Northern Great Plains piping plovers were marked with
band combinations identifiable to study area (see Table 1). Although most of these banding
studies were designed for other purposes, they nonetheless provide useful information for
this analysis.
None of the >5,000 Northern Great Plains piping plovers banded between 1982 and 2007 has
been reported breeding in the Great Lakes (E. Roche and F. Cuthbert, University of
Minnesota, pers. comm. 2008) 1 . Likewise, no Great Lakes piping plovers have been detected
breeding on the Northern Great Plains, although two birds carrying identifiable Great Lakes
brood markers have been reported at Lake of the Woods, Minnesota, during the spring
migration (since these birds were not uniquely marked, their subsequent recruitment into the
Great Lakes population cannot be positively confirmed).
The absence of observed exchanges is particularly significant in the context of very intensive
sustained monitoring, especially on the Great Lakes. Roche et al. (2008) reported a 96%
probability of detecting a banded adult breeding in the Great Lakes. Thus, the chance that a
dispersing bird banded on the Northern Great Plains would be missed in the Great Lakes is
extremely low. Furthermore, 94% of adults breeding on the Great Lakes as of 2007 were
banded (E. Roche pers. comm. in LeDee 2008), as were more than 95% of chicks surviving
to fledging, 2003-2007 (E. Roche pers. comm. 2009). Although annual survey coverage on
the Northern Great Plains is less complete, it is striking that no piping plovers banded in the
Great Lakes have been observed. Three comprehensive International Piping Plover Censuses
have been conducted since the initiation of Great Lakes banding in 1993. Furthermore, the
core area of the U.S. alkali lakes, as well as the Missouri River and most rivers and reservoirs
in Nebraska, have been surveyed annually since at least 1994 (C. Aron, USFWS, pers.
comm. 2009). In Manitoba, piping plovers have been counted annually since 1986, including
complete coverage of all known occupied habitat in 2006-2008 (J.P. Goossen, CWS, pers.
comm. 2009). Intensive searches were conducted in conjunction with a large scale banding
study in Saskatchewan, 2002-2008 (C. Gratto-Trevor, Environment Canada, pers. comm.
2008).
The large number of banded hatch-year birds (436 and 3,826 from the Great Lakes and
Northern Great Plains, respectively) is also an important consideration, because their
dispersal rates and distances from natal sites are much higher than inter-year movements of
1 A Manitoba piping plover observed on Lake Erie in August, 1986 (Haig and Oring 1988b) was later
determined to be a migrant (J. Dingledine, USFWS, pers. comm. 2009).
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