Seabird Research and Monitoring Needs in Northwestern México1 Eduardo Palacios2 and Lucía Alfaro3 ________________________________________ Abstract Seabird research in northwestern México has increased in percent of the marine area and almost all the islands in the last 20 years, however many areas remain unexplored northwestern México, including those holding major and seabird colony inventories are badly needed. Coastal seabird colonies, are federally protected under different wetlands and adjacent islands from southern Sonora categories of natural protected areas, such as Biosphere through Nayarit host large colonies of pelecaniforme and Reserve, National Park, and Area for Protection of other seabirds, but surveys of these areas have been Flora and Fauna. In addition, there is a proposal to limited and localized. Seabird colonies on islands in the protect the Pacific islands off Baja California (B. Gulf of California and off the west coast of the Baja Tershy, pers. comm.). California peninsula have been well documented but only for surface nesting species. Population abundance esti- Management plans to these areas involve scientific re- mates for sub-surface nesting species are almost non- search and monitoring as the key instruments for the man- existent although recent projects are beginning to address agement of the whole protected area. Based on the this issue. Monitoring in México is basically limited to 10 concept of adaptive management, applied research and species: Brown Pelicans (Pelecanus occidentalis), monitoring will be the base for the evaluation and perma- Double-crested Cormorants (Phalacrocorax auritus), nent adaptation of management practices implemented in Blue-footed (Sula nebouxi) and Brown boobies (S. the reserve. Associated actions include the creation of leucogaster), Heermann´s Gull (Larus heermmanni), databases linked to Geographical Information Systems. Royal (Sterna maxima), Elegant (S. elegans), Gull-billed Hence, the importance of establishing research priorities (S. nilotica) and Least Tern (S. antillarum), and Xantus´s applied to management and to start an inter-institutional, Murrelet (Synthliboramphus hypoleucus) in a few colo- long-term seabird-monitoring program in different nies. It is essential to develop a network of institutions and regions. researchers to do monitoring and research. Here, we provide an overview of seabird research and monitoring Seabird monitoring is the accumulation of time series status and needs in northwestern México and conservation data on any aspect of seabird distribution, abundance, actions that are being done for the conservation of demography, or behavior of seabirds (S. Hatch, pers. seabirds in this region. comm.). Its importance has been largely overlooked both by researchers and managers, and therefore, if funded, monitoring programs are usually underfunded. Monitoring is important in determining the welfare of Key words: conservation, islands, monitoring, north- seabird populations that may be affected by human western México, research needs, seabirds. activities or use of marine resources. But equally im- portant is the role of seabirds as indicators of environmental change. There is ample evidence that Introduction seabirds respond manifestly to oceanographic varia- tions such as El Niño-Southern Oscillation and lesser Seabird conservation is mostly a matter of island oceanic and atmospheric events (e.g. Ainley et al. conservation (D. W. Anderson, pers. comm.). About 4 1986; Sydeman et al. 2001), thus enhancing the relevance of seabird monitoring in an era when global __________ change is a growing concern. In addition, fishery managers are realizing that seabirds can serve as cost- 1 A version of this paper was presented at the Third Interna- effective samplers of fish stocks (e.g., Anderson et al. tional Partners in Flight Conference, March 20-24, 2002, 1980; Cairns 1987, 1992; Sunada et al. 1981). In Asilomar Conference Grounds, California. 2CICESE en BCS. Miraflores 334 e/ Mulegé y La Paz. Fracc. ecology, observational data obtained passively can be Bella Vista. La Paz, Unidad La Paz. 23050 MÉXICO. Tel/Fax: important for community experiments requiring great (52) 612-121-3031 U.S. mailing address: P.M.B. 1177, 482 W. numbers of relevant simultaneous variables, often on a San Ysidro Blvd #2, San Ysidro, CA 92173. E-mail: great scale, and long time periods to render the [email protected] information more significant. Thus, seabird monitoring 3Afegua, A.C. Av. 3 Sur # 8. Fracc. El Comitán, La Paz, B.C.S. 23201 México. may be important for testing of various hypothesis USDA Forest Service Gen. Tech. Rep. PSW-GTR-191. 2005 151 Seabird Research and Monitoring – Palacios and Alfaro regarding environmental or human causes of popula- populations of Black (70 percent) and Least (90 tion dynamics. percent) storm-petrels, Blue-footed Booby (40 percent), Heermann´s (90 to 95 percent) and Yellow- The objective of this paper is to review seabird research footed (100 percent) gulls, Elegant Tern (95 percent), and monitoring needs in northwestern México (fig. 1). We and Craveri´s Murrelet (S. craveri) (90 percent) breed emphasize the need for long-term breeding seabird in the region. All these taxa, plus Black-vented Shear- monitoring programs in different regions or protected water (Puffinus opisthomelas), and Xantus´s Murrelet areas to provide management agencies the necessary are endemic or quasi-endemic to the region (Howell information for better-informed decision-making. 2001). The region also hosts the world´s largest Brown Pelican and Brown Booby colonies (D. W. Anderson, 3 1983). At least 40 species of seabirds breed on the 1 4 islands and coastal wetlands in northwestern México (Everett and Anderson 1991, Howell and Webb 1995). 2 Methods EEZ In 1998, consigned by the Pacific Seabird Group, we initiated a survey and compilation of past and present N 5 effort to monitor Pacific seabirds in México. Through literature review and applying a questionnaire to key seabird researchers in the region we focused on past and present efforts to monitor Pacific seabirds — which species have been monitored, where, what para- Figure 1— The region of northwestern México. It includes meters have been measured, and who has done the the peninsula of Baja California that comprises the states work? We plan to continue this survey in the future of Baja California (1) and Baja California Sur (2), the main- because updated on an annual or more frequent basis, land states of Sonora (3), Sinaloa (4), and Nayarit (5), and the Economic Exclusive Zone (EEZ), including the Gulf of this information will permit a continuing evaluation of California and its associated islands. where we have been in seabird monitoring, where we would like to go, and what we need to do to get there. Here, we considered a total of 70 seabird projects Overview conducted since 1970 that included some sort of The region of northwestern México includes the penin- monitoring. In addition, we reviewed a list of more sula of Baja California, the states of Sonora, Sinaloa, than 200 published and unpublished reports that and Nayarit, the Gulf of California, the Economic include potential data on seabirds of northwestern Exclusive Zone (200 nautical miles, expanded by Isla México. Guadalupe in the north and by Isla Clarión in the south), and its associated islands (fig. 1). This region comprises an important area for seabirds. Specific Results information on seabirds distribution and conservation needs in northwestern México has been published in Seabird colonies on islands in the Gulf of California three major summaries: Anderson (1983), Everett and and off western Baja California peninsula have been Anderson (1991), and Velarde and Anderson (1994). well documented but only for surface nesting species. As important, however, are also two books that cover Population abundance estimates for sub-surface nesting the region: Wilbur (1987) and Howell and Webb species such as storm petrels and murrelets are very (1995), as well as numerous recently published species few although recent projects (such as the U.S. accounts (e.g., Carter et al. 1995; Erickson and Howell Geological Survey [USGS] and Island Conservation 2001; Massey and Palacios 1994; Mellink 2001; and Ecology Group [ICEG] surveys, see below) are Molina and Garrett 2001; Palacios and Mellink 1996, addressing this gap of knowledge. Monitoring in 2000; Pitman 1986; Rebón-Gallardo 2000, and others). México is very modest and systematic seabird monitor- The major ornithological journal on seabirds from the ing is limited to ten species in few colonies: Brown region has been Western Birds (Western Field Orni- Pelicans, Double-crested Cormorants, Blue-footed and thologists). Brown boobies, Heermann´s Gull, Royal, and Elegant, Gull-billed and Least Tern, and Xantus Murrelet. Some particularly noteworthy remarks regarding the importance of the region to seabirds include the fol- In the last 30 years, more than 100 researchers (77 lowing examples: A large percentage of the world Mexicans and 33 Americans) have been and/or are USDA Forest Service Gen. Tech. Rep. PSW-GTR-191. 2005 152 Seabird Research and Monitoring – Palacios and Alfaro conducting Pacific seabirds research in México. Based 4. Since at least 1980, H. Drummond and students on the responses to the survey and on the literature (UNAM) have been and are currently investigating documentation, 55 species of seabirds have been moni- seabird behavior in Isla Isabel, Nayarit. tored in México, but the extent