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. . Area Manager DRAFT 24 disturbance, although this may only be temporary, and patches may cycle back into suitability. Therefore, a suitable habitat patch, either occupied or unoccupied, may not remain continuously - -.".-- . - 1._ ..II. _ _.__',,-._1-1_ _____...1. _ 1___..._ 'T_~~~n_:""A ....:+...l..1"" l.....\...:.....+ n.:ll .....o..."".fnro nl':l" !:II U'-'l,;Upn:u i::UIUJUl SUIL.iCLUIC U\lCl WIt:; lUllb-l~.llJ1. UUU"''''Up.l~ .::tU.lLUVH... UUVU..UL nUl LU....................... t".....J - vital role in the recovery of the flycatcher, because it will provide suitable areas for breeding flycatchers to colonize as the population expands or fol1owing loss or degradation of existing breeding sites (U.S. Fish and Wildlife Service 2002). Indeed, many sites will likely pass through a stage of being suitable but unoccupied before they become occupied. Potential habitats that are not currently suitable will also be essential for flycatcher recovery, because they are the areas from which new suitable habitat develops as existing suitable sites are lost or degraded. Potential habitats are the areas where changes in management practices are most likely to create suitable habitat. Therefore, habitat management for recovery of the flycatcher must include developing and/or maintaining a matrix of suitable and potential riparian patches within a watershed so that sufficient suitable habitat will be available at any given time (U.S. Fish and Wildlife Service 2002). Breeding Biology. Throughout its range the flycatcher arrives on breeding grounds in late April and May (Sogge and Tibbitts 1992; Sogge et aI. 1993; Muiznieks et al. 1994; Sogge and Tibbitts 1994; Maynard 1995; Sferra et al. 1995, 1997). Nesting begins in late May to early June and young fledge from late June through mid-August (Willard 1912; Ligon 1961; Brown 1988a,b; Whitfield 1990; Sogge and Tibbitts 1992; Sogge et al. 1993; Muiznieks et al. 1994; Whitfield 1994; Maynard 1995). Flycatchers typical1y lay three to four eggs per clutch (range = I - 5). Eggs are laid at one-day intervals and are incubated by the female for approximately 12 days (Bent 1960, Walkinshaw 1966, McCabe 1991). Young fledge approximately 12 to 13 days after hatching (King 1955, Harrison 1979). Typical1y one brood is raised per year, but birds have been docwnented raising two broods during one season and re-nesting after a failure (Whitfield 1990, Sogge and Tibbitts 1992, Sogge et aI. 1993, Sogge and Tibbitts 1994, Muiznieks et al. 1994, Whitfield 1994, Whitfield and Strong 1995). The entire breeding cycle, from egg laying to fledging, is approximately 28 days. Flycatcher nests are fairly small (3.2 inches tall and wide) and are commonly placed in a shrub or tree. Nests are open cup structures, and are typical1y placed in the fork of a branch. Nests have been found against the trunk of a shrub or tree (in monotypic saltcedar and mixed native broadleaflsaltcedar habitats) and on limbs as far away from the trunk as 10.8 feet (Spencer et al. 1996). Typical nest placement is in the fork of small-diameter (e.g., 0.4 in), vertical or nearly vertical branches (Service 2002). Occasionally, nests are placed in down-curving branches. Nest' height varies considerably, from 1.6 to 60 feet, and may be related to height of nest plant, overal1 canopy height, and/or the height of the vegetation strata that contain smal1 twigs and live growth. Most typically, nests are relatively low, 6.5 to 23 feet above ground. Flycatcher nests in box elder dominated habitats are highest at almost 60 feet (Service 2002). The flycatcher is an insectivore, foraging in dense shrub and tree vegetation along rivers, streams, and other wetlands. The bird typical1y perches on a branch and makes short direct flights, or sallies to capture flying insects: Drost et aJ. (1998) found the major prey items of the flycatcher (in Arizona and Colorado) consisted of true flies (Diptera); ants, bees, and wasps (Hymenoptera); and true bugs (Hemiptera). Other insect prey taxa included leafhoppers OUH14