Mendoza Luis Francisco, Carmona Roberto
Departamento Académic de Biologia Marina, Universidad Autónoma de Baja California Sur, Apartado postal 19-B, La Paz, Baja California Sur, CP 23080, México.
Rev Biol Trop. 2013 Mar;61(1):229-41.
Baja California Peninsula has several wetlands that represent important ecosystems for shorebirds. San Ignacio Lagoon is one of these sites, and supports 10% of the total abundance of shorebirds reported in this Peninsula. Since there is few information about this group in this area, we studied spatial and temporal changes in abundance and distribution of shorebirds in San Ignacio Lagoon. For this, we conducted twelve monthly censuses (October 2007-September 2008) on the entire internal perimeter of the lagoon, which we divided into four areas: two at the North and two at the South. We observed a seasonal pattern, with the lowest abundance in May (1 585 birds) and the highest in October (47 410). The most abundant species were Marbled Godwits (Limosa fedoa; 55% of the total records), Western Sandpipers (Calidris mauri; 23%), and Willet (Tringa semipalmata; 10%). All three species were more abundant in autumn; for both, the Marbled Godwit and Willet, we observed their highest numbers in winter and spring, while the Western Sandpiper showed noticeable oscillations, reaching a maximum in early winter (December). In summer, Marbled Godwit and Willet were the only birds present but in lower numbers. Here present the first records of the Pacific Red Knot (Calidris canutus roselaari) in the area. Bird abundance and species richness were influenced seasonally by migration and spatially by sites in the lagoon. The greatest shorebird abundance was in the South area of the lagoon, probably because of better accessibility to food. Our results allowed the inclusion of San Ignacio Lagoon in the Western Hemisphere Shorebirds Reserve Network (WHSRN) as a site of international importance.
下加利福尼亚半岛有几个湿地，这些湿地是滨鸟的重要生态系统。圣伊格纳西奥泻湖就是其中之一，该半岛记录的滨鸟总数中有10%在此栖息。由于该地区关于这一鸟类群体的信息很少，我们研究了圣伊格纳西奥泻湖滨鸟数量和分布的时空变化。为此，我们对泻湖的整个内周边进行了12次月度普查（2007年10月至2008年9月），我们将其分为四个区域：北部两个区域和南部两个区域。我们观察到一种季节性模式，5月份数量最少（1585只鸟），10月份数量最多（47410只）。数量最多的物种是斑尾塍鹬（Limosa fedoa；占总记录数的55%）、西部滨鹬（Calidris mauri；占23%）和长嘴半蹼鹬（Tringa semipalmata；占10%）。这三个物种在秋季数量都更多；对于斑尾塍鹬和长嘴半蹼鹬来说，我们观察到它们在冬季和春季数量最多，而西部滨鹬则呈现出明显的波动，在初冬（12月）达到最大值。在夏季，只有斑尾塍鹬和长嘴半蹼鹬，但数量较少。这里首次记录了该地区的太平洋红腹滨鹬（Calidris canutus roselaari）。鸟类数量和物种丰富度受季节性迁徙影响，在空间上受泻湖内不同地点的影响。滨鸟数量最多的是泻湖的南部区域，可能是因为那里更容易获取食物。我们的研究结果使得圣伊格纳西奥泻湖被纳入西半球滨鸟保护区网络（WHSRN），成为具有国际重要性的地点。
