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Elucidating spatio-temporal movements of animals is an integral component of wildlife conservation and protected species management. Between 2008 and 2010 we satellite tracked 15 adult female hawksbill turtles Eretmochelys imbricata in the eastern Pacific Ocean to evaluate their movement behavior and to guide management and conservation efforts of this highly endangered population. Movements and habitat use were highly neritic, and post-nesting mi g - ration distances (maximum = 283.11 km) were short relative to migrations of other sea turtle species. In foraging areas, the majority of hawksbills established restricted, inshore home ranges within mangrove estuaries. A large proportion (>65%) of turtle location points fell within protected areas, although many of these sites lack enforcement and monitoring. The consistent use of estuar- ine and mangrove habitat for nesting and foraging may explain why hawksbills went virtually un- detected in the eastern Pacific for decades. The spatially restricted and neritic life cycles of adult hawksbills in the eastern Pacific highlight threats (e.g. overlap with coastal fisheries, increased sus- ceptibility to habitat degradation and/or catastrophic events) and opportunities for conservation (e.g. acute conservation target areas, less variant jurisdictional boundaries/regulations) for this spe- cies. Our results underscore the importance of strengthening protected area management, man- grove estuary protection and hawksbill research and conservation in the eastern Pacific.

El Salvador has a series of nesting beaches that together host the highest remaining nesting abundance of hawksbill turtles Eretmochelys imbricata in the eastern Pacific Ocean. How- ever, the distribution of hawksbill turtle nesting and causes of hawksbill mortality along the Salvado- ran coast are yet to be described. Here, we report on life history information of this population, in - cluding body size of nesting hawksbill turtles and clutch size, and mortality along nesting habitat at the following 3 areas in El Salvador: Los Cobanos Reef Marine Protected Area (Los Cobanos), Bahia de Jiquilisco-Xiriualtique Biosphere Reserve (Bahia), and Punta Amapala. In 2008, we recorded 310 nesting events by hawksbill turtles over 51.6 km of nesting habitat, giving an overall nesting density of 6.0 nests km -1 ; nearly 62% of total nesting activity and the highest reproductive output occurred in the Bahia. Morphometric data were collected from 26 nesting turtles that ranged from 74 to 88 cm curved carapace length (mean ± SD; 81.6 ± 3.6 cm) and 63 to 76 cm curved carapace width (70.1 ± 3.4 cm). Between 2004 and 2008, a total of 24 hawksbill turtles died in the mangrove and estuarine habitats of the Bahia (18 attributed to blast fishing) and in 2008, 8 hawksbill turtles died due to bycatch in bottom-set gillnets in Los Cobanos. Given the severely depleted status of hawksbill turtles in the eastern Pacific, conservation action is urgently needed to mitigate their incidental capture in artisanal fisheries gear at primary nesting and foraging areas in El Salvador.

While little is known about hawksbill turtlesEretmochelys imbricatain the eastern Pacific Ocean, available information suggests that the population has declined substantially in recent decades and could be near extirpation in the region. To evaluate the current status of the population more effectively and to determine the feasibility of recovery efforts, a workshop of regional marine turtle specialists was held in June 2008 in Los Cóbanos, El Salvador. An international working group, Iniciativa Carey del Pacífico Oriental (ICAPO; Eastern Pacific Hawksbill Initiative in English), was established to consolidate information, promote conservation projects and raise awareness about the species. We present information derived from the workshop and compiled by the ICAPO working group since that time. Considering only records from 1 January 2007 to 31 May 2009 it appears that El Salvador hosts the majority of known hawksbill turtle nesting activity in the eastern Pacific, with 79.6% (n = 430) of all nesting observation records, and Mexico hosts the majority of records of hawksbill turtles at sea, with 60.3% (n = 44) of all in-water observation records. Although current abundance is very low, the pervasiveness of the species in the region suggests potential for conservation and recovery. Despite a historical paucity of research focusing on this population, the relatively large and steadily increasing number of records as a result of concerted efforts demonstrates the viability of the ICAPO network as an instrument to promote conservation of this species in the eastern Pacific.

Adult hawksbill turtles ( Eretmochelys imbricata ) are typically described as open-coast, coral reef and hard substrate dwellers. Here, we report new satellite tracking data on female hawksbills from several countries in the eastern Pacific that revealed previously undocumented behaviour for adults of the species. In contrast to patterns of habitat use exhibited by their Caribbean and Indo-Pacific counterparts, eastern Pacific hawksbills generally occupied inshore estuaries, wherein they had strong associations with mangrove saltwater forests. The use of inshore habitats and affinities with mangrove saltwater forests presents a previously unknown life-history paradigm for adult hawksbill turtles and suggests a potentially unique evolutionary trajectory for the species. Our findings highlight the variability in life-history strategies that marine turtles and other wide-ranging marine wildlife may exhibit among ocean regions, and the importance of understanding such disparities from an ecological and management perspective.

Collections of 11 species of shallow water Polyplacophora from El Salvador were made in July 2002. Previously only five species had been documented in El Salvador: Chaetopleura lurida (Sowerby, 1832); Ischnochiton guatemalensis (Thiele, 1910); Ceratozona angusta (Thiele, 1909); Chiton stokesii (Broderip, 1832) and Acantochitona exquisita (Pilsbry, 1893). Of these, L. guatemalensis and A. exquisita were not collected in this census. Seven other species are reported here for El Salvador for the first time: Lepidochitona beanii (Carpenter, 1857); Ischnochiton dispar (Sowerby, 1832); Stenoplax limaciformis (Sowerby, 1832); Callistochiton expressus (Carpenter, 1865); Acanthochitona arragonites (Carpenter, 1867); A. ferreirai (Lyons, 1988) and A. hirudiniformis (Sowerby, 1832). The known geographic distribution of 1. dispar is extended to the north. An un-named species of Lepidochitona is briefly described.

En El Salvador se habían registrado los poliplacóforos Chaetopleura lurida (Sowerby, 1832); Ischnochiton guatemalensis (Thiele, 1910); Ceratozona angusta (Thiele, 1909); Chiton stokesii (Broderip, 1832) y Acantochitona exquisita (Pilsbry, 1893). Recolectamos quitones en aguas someras de El Salvador en julio del 2002, agragando a la lista a Lepidochitona beanii (Carpenter, 1857); Ischnochiton dispar (Sowerby, 1832); Stenoplax limaciformis (Sowerby, 1832); Callistochiton expressus (Carpenter, 1865); Acanthochitona arragonites (Carpenter, 1867); Acanthochitona ferreirai (Lyons, 1988) y Acanthochitona hirudiniformis (Sowerby, 1832). Ampliamos la distribución documentada de I. dispar hacia el norte y describimos brevemente una especie innominada de Lepidochitona.Chitons (Mollusca: Polyplacophora) from El Salvador, Central America. Collections of 11 species of shallow water Polyplacophora from El Salvador were made in July 2002. Previously only five species had been documented in El Salvador: Chaetopleura lurida (Sowerby, 1832); Ischnochiton guatemalensis (Thiele, 1910); Ceratozona angusta (Thiele, 1909); Chiton stokesii (Broderip, 1832) and Acantochitona exquisita (Pilsbry, 1893). Of these, I. guatemalensis and A. exquisita were not collected in this census. Seven other species are reported here for El Salvador for the first time: Lepidochitona beanii (Carpenter, 1857); Ischnochiton dispar (Sowerby, 1832); Stenoplax limaciformis (Sowerby, 1832); Callistochiton expressus (Carpenter, 1865); Acanthochitona arragonites (Carpenter, 1867); A. ferreirai (Lyons, 1988) and A. hirudiniformis (Sowerby, 1832). The known geographic distribution of I. dispar is extended to the north. An un-named species of Lepidochitona is briefly described. Rev. Biol. Trop. 55 (1): 171-176. Epub 2007 March. 31.