Demography and seasonal movement patterns of band-tailed pigeons in New Mexico
The band-tailed pigeon inhabits mountainous terrain across its North American range making it difficult to obtain detailed life history information. During the late 1960’s through the 80’s, however, there was a great deal of effort invested by a small handful of biologists to describe the movement, demographics, and natural history of interior “Four Corners” populations of band-tailed pigeons through field and captive studies (Gutíerrez et al. 1975, Stabler et al. 1977, White and Braun 1978, Curtis and Braun 1983, Kautz and Braun 1983, White and Braun 1990, Keppie and Braun 2000 and references therein). Much of the data gathered during this period represents the only data available on this population to inform biologists on the conservation and management of this migratory game bird species.
In the 20-30 years following, much of the research has primarily focused on the Pacific Coast population (Jarvis and Passmore 1992, Keppie and Braun 2000, Sanders and Jarvis 2000, Sanders and Jarvis 2003, Cassaza et al. 2005) and discoveries of frequently visited mineral sites and increased banding programs have led to improved estimates of population status and comparisons with harvest data (Jarvis and Passmore 1992, Sanders and Jarvis 2000, Cassaza 2005, Sanders 2012). Coupled with banding programs and utilization of modern tracking techniques, our understanding of population dynamics and seasonal movement patterns have greatly improved for this population (Leonard 1998, Sanders 2012). To better inform conservation/management decisions for the Four Corners population, renewed efforts describing current population status, distribution, demography, and seasonal movement patterns in relation to food availability are needed to balance our knowledge of this species across its range (Braun 1994).
To guide future work on this species, the Migratory Shore and Upland Game Bird Support Task Force recently produced updated research priority needs for band-tailed pigeons (Case et al. 2011). Their recommendations focused on 1) providing reliable demographics and 2) understanding the association of food availability with abundance and distribution of band-tailed pigeons. Recent research efforts to study band-tailed pigeons in Arizona and interest by new research/management personnel in New Mexico (proposal authors), has created a perfect opportunity to increase our current understanding of interior populations and inform resource managers by combining past and present knowledge.
To meet these research needs, we have secured three capture/banding sites across New Mexico (Figure 1) where we are conducting a long-term banding and PIT tagging program to provide more reliable demographic estimates for band-tailed pigeons in New Mexico. Acquiring accurate annual survival rate estimates are critical to developing and maintaining management strategies. Because harvest is a management tool and may represent a potential effect on population dynamics, estimates of recovery rates are important for assessing the effects of harvest on population dynamics (Nicolai et al. 2005).
Additionally, describing the relationship between food availability with abundance and distribution is difficult when no current data exists on the seasonal movement patterns of these birds. So, in conjunction with our banding efforts, we are investigating the use of low cost geolocator units for describing seasonal movement patterns (Stutchbury 2009, Bridge et al. 2011). Our long-term goal is to build upon the results of this study and use this data to initiate future studies looking at the relationship between movement and food availability, wintering ground distribution, and more detailed natural history for New Mexico band-tailed pigeons.
By pairing a long-term banding study with information on daily and seasonal movements, we believe results from our work will produce the following outcomes:
- Demographic analysis of band tailed pigeon populations in New Mexico using band and PIT tag data
- Increased understanding of band tailed pigeon daily and seasonal movement patterns across New Mexico
- Increased knowledge of interior band-tailed pigeon nesting and wintering ecology
- Increased knowledge of movement patterns that could lead to the development of long-term monitoring sites in New Mexico,
- Dan Collins, Regional Migratory Game Bird Coordinator, U.S. Fish and Wildlife Service, Region 2, Migratory Bird Office
- Scott Carleton, Assistant Unit Leader, U.S. Geological Survey, New Mexico Cooperative Fish and Wildlife Research Unit, New Mexico State University