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survived the non-breeding season. The project area is important to merlin regardless of
the species not nesting there.

Burrowing owl

According to BonTerra Psomas (2015, Attachment F:2), burrowing owls show high nest
site fidelity, often using the same burrows for nesting year after year. No citation to
source accompanied this conclusion. In my research of burrowing owl nest site fidelity, I
have found very low site fidelity over six years of monitoring at Dixon National Radio
Transmission Facility, 13 years of monitoring at Lemoore Naval Air Station, 17 years of
monitoring in Davis, California, and 9 years of monitoring in the Altamont Pass Wind
Resource Area. Some nest sites are indeed used over several years, but most are not
used again in immediately succeeding years. In fact, among 46 randomly selected plots
averaging about 54 ha per plot, nest densities in any given year can predict the densities
the following year, but not after 2 or 3 years (Figure 2). Breeding pairs of burrowing
owls shift breeding locations often, resulting in a shifting mosaic pattern of abundance
that defies any notion of high nest site fidelity.

Breeding pairs in 2012 Breeding pairs in 2013 Breeding pairs in 2014
18 16 16
0
16 14 14
14 12 12 0
12
10 10
10
0 8 0 8 0
8
0 0
6 6
6 0
0 0
00 0 4 4
4 0 0
0 0
2 0 2 0
0 0
0
0 2 4 6 8 10 12 14 16 18 2 4 6 8 10 12 14 16 2 4 6 8 10 12 14 16
Breeding pairs in 2011 Breeding pairs in 2011 Breeding pairs in 2011
Breeding pairs in 2015 Breeding pairs in 2016
16·~~~~~~~~~~ 8~~~~~~~~~~
14 7
12 6
1 5
8 0 4
6 3 0
0
4 2 0
2 l ' 0
o.0-4'-e--<._....--4~~~~~--' 0 -
0 2 4 6 8 10 12 14 16 0 1 2 3 4 5 6 7 8
Breeding pairs in 2011 Breeding pairs in 2011

Figure 2. Breeding pairs of burrowing owls among plots in theAPWRAfrom 2012
through 2016 as functions of breeding pairs in 2011 (Smallwood, unpublished data).

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