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. . Area Manager DRAFT 26 to 34 percent of returning birds moved to different sites (Luff et al. 2000). In 2001, 75 percent of adults known to have survived from 2000 returned to the same breeding site (Kenwood and n.___, ............., , "111___L d____ _.._-=..:__1....:_..1...1_ _ ")0\ t..............1""';I...... O^n~"."".lt T o::.\.-p rptnT'nM tn thp. rC:L\lUIl L.UUI). 1"\.U UUL U1J~ ~w \'lVU15 V.u.U03 \U - ",",VI vu..au.,"^"...... ......vv...........u ............... ..._._..__ ._ -- ." area the next year (Kenwood and Paxton 2001). Although flycatcher territory fidelity appears to be high, they can regularly move among sites within and between years (Kenwood and Paxton 2001). Within-drainage movements are more common than between-drainage movements (Kenwood and Paxton 2001). Year-to-year movements of birds have been detected between the San Pedro/Gila River confluence and Roosevelt Lake; the Verde River near Camp Verde and Roosevelt Lake; and the Little Colorado River near Greer and Roosevelt Lake (Kenwood and Paxton 200 I). Typical distances moved range from 1.2 to 18 miles. However, long-distance movements of up to 137 miles have been observed on the lower Colorado River and Virgin River (McKernan and Braden 2001). Flycatchers are believed to function as a group of metapopulations and their survival and recovery are dependent on well-distributed populations in close proximity (U.S. Fish and Wildlife Service 2002). Esler (2000) describes Levins' metapopulation theory as addressing the demography of distinct populations (specifically extinction probabilities), interactions among subpopulations (dispersal and recolonization), and ultimately persistence of the aggregate of subpopulations, or the metapopuJation. Metapopulation theory has been applied increasingly to species whose ranges have been fragmented. An incidence function analysis completed for the flycatcher incorporated a spatial component to estimate probabilities of habitat patch extinction and colonization (Lamberson et a!. 2000). Modeling indicated that persistence of flycatcher populations is reduced when populations are small and widely distributed. Conversely, metapopulations are more stable when subpopulations are large and close together. However, where populations exceed 25 pairs, the effects of catastrophic events (e.g., fire, disease, flood, etc.) are magnified. Rangewide, the flycatcher population is comprised of extremely small, widely-separated breeding groups, including unmated individuals. In 2001, approximately 40 to 50 percent of 986 territories throughout the subspecies range were located at three locations (CliIDGila Valley- NM, Roosevelt Lake - AZ, San Pedro/Gila confluence - AZ). In Arizona, 63 percent of the sites (n = 46) where flycatchers were found in 2001 (Smith et a!. 2002) were comprised of 5 or fewer territories. In Arizona during the 2001 season, all but the "Salt River Inflow" site at Roosevelt Lake had 20 pairs or less (Smith et al. 2002). Rangewide, 76 percent of all sites from 1993 to 2001 had 5 or less flycatcher territories present at the site (Sogge et al. 2002). Across the bird's range, there are fewer than six sites with greater than 50 territories (Sogge et al. 2002). The distribution of breeding groups is highly fragmented. For example, in New Mexico the flycatchers at Los Ojos on the Rio Chama are approximately 60 miles from the closest known site at San Juan Pueblo, and the Radium Springs site is approximately 70 miles south of the flycatchers at San Marcial. The large distances between flycatcher breeding groups and small population sizes decrease stability and increase the risk of local extirpation due to stochastic events, predation, cowbird parasitism, and other factors (U.S. Fish and Wildlife Service 2002). Having 40 to 50 percent of the entire subspecies at just three locations could have dire effects on the species should OOH25