Priorities for Future Research

Conducting long-term studies of breeding populations in representative parts of North American range to determine key demographic parameters including age structure, survival and recruitment, and annual and lifetime reproductive performance, is a very high priority. Assessments to include breeding populations at both high-arctic interpres (high-arctic Canada, Greenland) and low-arctic morinella (low-arctic Canada, Alaska) locations. Detailed comparisons of timing of breeding, condition at arrival, energy expenditures, and constraints (physiology) during breeding, breeding performance and behavior (including site and mate fidelity), and timing and condition at departure (age-specific) should be considered, as well as other fundamental demographic parameters such as population size, age composition of breeding birds, age of first breeding, life span and reproductive output of individuals. Determinants of breeding success, particularly habitat and food/energy requirements, should be examined, including critical staging sites immediately before and after breeding. Special emphasis should also be given to elucidating possible causal relationships of energy expenditure to breeding performance, survival/longevity, and site fidelity, as well as requirements for self-maintenance. There is also a need to further examine geographical variation in morphology, plumage, and character differences between the sexes and age cohorts.

Much more also needs to be done on aspects of migration and the ecological requirements during migration and on the wintering grounds. Particular attention should be directed at defining major spring and fall migration routes of North American breeding populations, both spatially and temporally, with emphasis given to timing of movement (general and age-specific), relative magnitude of movement, and identification of stopover sites and their biological attributes and long-term use by this species. More is known about movements of high-arctic interpres population than low-arctic morinella turnstones along the Atlantic and Pacific coastal flyways and smaller interior route, but serious gaps exist for both North American populations. Clearly, this requires further study to provide essential information of the biology of this species and to better identify threats and conservation needs (see Conservation and management, above).

Ecological requirements for successful over-wintering and growth and development at the wintering grounds are poorly known for all age groups, especially in South America. Time and energy budgets in relation to molt and preparation for spring migration need further study, as does measurement of growth and postfledging-survival rates from first arrival at wintering location to subsequent movement toward breeding area at 2 yr of age. More information is needed on known and suspected threats to this species throughout its range, including degradation of coastal ecosystems, direct interactions with humans related to hunting (winter quarters and during migration), habitat disturbance and destruction (mostly winter quarters and staging areas; also to a lesser extent on breeding grounds by researchers), and toxic and chemical contamination (levels and effects poorly known, but probably significant on wintering grounds and parts of migratory routes). Immediate action is required to establish a long-term biological monitoring research program to: determine population size and status (i.e., in equilibrium or not), identify essential ecological requirements, assess and mitigate human-induced factors of mortality, and provide protection to land areas and resources critical to the species’ future welfare and survival.