|Scientific Name:||Heterodontus mexicanus|
|Species Authority:||Taylor & Castro-Aguirre, 1972|
|Taxonomic Notes:||Heterodontus mexicanus co-exists with H. francisci in the Gulf of California and these species may be confused in the field. Records from the South American part of its range could be confused with H. quoyi.|
|Red List Category & Criteria:||Data Deficient ver 3.1|
|Reviewer/s:||Kyne, P.M., Cavanagh, R.D. & Fowler, S.L. (Shark Red List Authority)|
A small (to 70 cm total length) inshore hornshark of rocky and sandy habitats and coral reefs. Endemic to the Eastern Pacific with a disjunct distribution in the Gulf of California and Mexican Pacific to Guatemala, Colombia and Panama and probably Ecuador and Peru. It is not known whether these areas support different subpopulations of the species. The Mexican hornshark is not of commercial value, but is taken as bycatch in bottom gillnets and shrimp trawling operations in the Gulf of California and Mexican coastal lagoons. Catches are discarded or sometimes retained for human consumption or fishmeal. Hornsharks are hardy species and can survive capture if returned to the water; however, catches in Mexico are often left to die on beaches. Eggs are laid in rocky areas unlikely to be impacted by fisheries. Insufficient information is available at present to assess the species beyond Data Deficient, however, the species is of potential concern due to its restricted disjunct distribution and artisanal and industrial fishing pressure.
|Range Description:||Eastern Pacific from Mexico to Colombia and probably also Ecuador and Peru (Compagno 2001). Known to be a common species in Magdalena Bay (Mexican Pacific), and also in the upper part of the Gulf of California.|
Native:Colombia; Guatemala; Mexico (Baja California, Baja California Sur); Panama
|FAO Marine Fishing Areas:||
Pacific – eastern central; Pacific – southeast
|Range Map:||Click here to open the map viewer and explore range.|
The species? distribution is disjunct and there may be several populations within its Mexican and Central American range. The southern America population could also be distinct.
No other information available on population sizes or structure.
|Habitat and Ecology:||
Found on the continental shelf from close inshore to 50 m depth, in rocky habitats including reefs and seamounts, as well as coral reefs, and sandy areas (Compagno 2001). Eggs are laid in rocky areas that would unlikely be impacted by fisheries (W. Smith pers. comm).
No detailed information on the species? biology, but like other hornsharks, is oviparous.
Feeds on demersal crabs and fishes.
Life history parameters
Age at maturity (years): Unknown.
Size at maturity (total length): Female: unknown; Male: 40 to 50 cm TL (Compagno 2001).
Longevity (years): Unknown.
Maximum size (total length): ~70 cm TL (Compagno 2001).
Size at birth: ~14 cm TL (Compagno 2001).
Average reproductive age (years): Unknown.
Gestation time (months): Unknown.
Reproductive periodicity: Unknown.
Average annual fecundity or litter size: Unknown.
Annual rate of population increase: Unknown.
Natural mortality: Unknown.
The Mexican Hornshark is not of commercial value, but is taken as bycatch in bottom gillnets and shrimp trawling operations in the Gulf of California and Mexican coastal lagoons (artisanal and larger scale industrial fisheries). Márquez-Farías (2002) documents H. mexicanus as comprising 1.53% of the catch of Sonora artisanal shark fishery in the northern Gulf of California. Large numbers (up to a thousand individuals) may be caught in a single gillnet set and are often left to die on the beach (Villavicencio Garayzar pers. obs). It should be noted that the species is hard to identify and some of these may be H. francisci given that the two species co-occur (W. Smith pers.comm.). Catches are discarded or sometimes used for human consumption, fishmeal or for their skins. No information is available on catches in other parts of the species? range, but it may be affected by artisanal and commercial fisheries.
The meat is sometimes used for human consumption, fishmeal and the skin is also sometimes utilized.
Like other hornsharks, Heterodontus mexicanus is a hardy species and can survive capture in drift and trawl nets. Individuals should be returned to the water if alive after capture and education is required to end the practice of leaving large numbers to die on the beach.
Further information on distribution, population structure (to determine if separate subpopulations exist across the species? disjunct range) and biology is required.
The development and/or implementation of National Shark Plans under the FAO IPOA-Sharks, where necessary.
Chirichigno, N.F. 1974. Clave para identificar los peces marinos del Perú. Informe Instituto del Mar del Perú 44: 387.
Compagno, L.J.V. 2001. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Vol. 2. Bullhead, mackeral and carpet sharks (Heterodontiformes, Lamniformes and Orectolobiformes). FAO species catalogue for fisheries purposes. No. 1. Vol. 2. FAO, Rome.
Compagno, L.J.V., Krupp, F. and Schneider, W. 1995. Tiburones. In: W. Fischer, F. Krupp, W. Schneider, C. Sommer, K.E. Carpenter, and V.H. Niem (eds). Guía FAO para la identificación de especies para los fines de la pesca. Pacífico Centro-Oriental. Volumen II, Vertebrados-Parte 1. pp: 647–743. FAO, Roma.
Franke, R. and Acero, A. 1991. Registros nuevos y comentarios adicionales sobre peces cartilaginosos del Parque nacional Natural Gorgona (Pacifico Colombiano). I. Tiburones. Trianea 4: 527–540.
IUCN. 2006. 2006 IUCN Red List of Threatened Species. www.iucnredlist.org. Downloaded on 04 May 2006.
IUCN SSC Shark Specialist Group. Specialist Group website. Available at: http://www.iucnssg.org/.
Márquez Farías, J.F. 2002. Tiburones del Golfo de California. In: Sustentabilidad y Pesca Responsable en México: evaluación y manejo 1999–2000. Instituto Nacional de la Pesca (SAGARPA). pp: 237–258.
Taylor Jr., L.R. 1972. A revision of the shark family Heterodontidae (Heterodontiformes, selachii). Ph.D. Thesis, University of California, San Diego, xiii+176pp. University Microfilms International.
Taylor Jr., L.R. and Castro-Aguirre, J.L. 1972. Heterodontus mexicanus, a new horn shark from the Golfo de California. Anales la Escuela Nacional de Ciencias Biologias 19(1–4): 123–143.
|Citation:||Garayzar, C.V. 2006. Heterodontus mexicanus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 16 April 2014.|