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<br />determination of the' fledging rate (Thompson 1982, Thompson <br />and Slack 1983). <br />115. Assess disDersal Datterns and ~enetic diversity. <br />Little is known about the interaction between coastal least <br />terns and the interior least tern. Boyd'and Thompson (1985) <br />found a nesting lea~t tern in Kansas which had been banded <br />as a chick on the T~xas coast. It would be useful to know <br />if coastal least ter~s serve as a reservoir to replenish the <br />interior least tern i population; and if the status of the <br />coastal least tern population determines the numbers and <br />distribution of interior least terns. Monitoring movements <br />of marked birds in major breeding areas will fill the gap in <br />our understanding of dispersal. Knowledge of how new nest <br />sites are colonized, and where new birds originated will be <br />useful in developing ,population management plans and models. <br />'116. Assess mortality. <br />Factors such as h~an disturbance, predation, and water <br />level regulation have reduced success of interior least tern <br />eggs and chicks (Maybr and Dryer 1990). Factors affecting <br />adult mortality, however, have never been fully addressed <br />for any part of the 'annual cycle. Predation is a problem <br />for some California ,and coastal least terns (Burger 1984, <br />Minsky 1980, Massey 1981) and the closely allied little tern <br />in Europe (Haddon and Knight 1983). During the breeding <br />season, predation on: interior least terns by coyote (Canis <br />latrans), crow (Corvl,js brachyrhvnchos), and raptors has been <br />reported (G. R. Ling~e, personal communication, Hill 1985, <br />Kirsch 1990, Mayer and Dryer 1990) and predation on nesting <br />adults by barred owls (llilJ!. Yll.tlA) has been recorded (Smith <br />and Renken 1990). Predation is significant on the Missouri <br />National Recreational River (U. S. Fish and Wildlife <br />Service, unpublished data). It is important to determine <br />the extent and cause of adult and juvenile mortality during <br />the breeding season.: <br />117. Further identify life historv parameters and develoD <br />DODulation models. i <br />Field studies of interior least terns should be carried out <br />without reducing reproductive success or site tenacity. <br />Future breeding studies only should be undertaken after <br />researchers have identified specific critical factors that <br />require resolution in order to rehabilitate the species. It <br />would be useful to c~mpile all available life history data <br />and develop a model t9 estimate potential population trends. <br />12. Assess status and distrib~tion for the mi~ration Deriod. <br />Less is known about the m~gratory ecology for the interior least <br />tern than for any other phase of the annual cycle. Migratory <br />routes have not been adequately described for spring or fall. It <br />is not known if interior least terns follow major river systems <br />during migration or if they migrate directly north and south. <br />Further, it is unknown if interior least terns join coastal least <br />terns prior to coastal least tern migration to Latin America or <br />if interior least terns h~ve their own migration route. Before <br /> <br />34 <br />