Humpback Whales

 

Essay by García-Velasco Carolina & López-Juarez Nadia Frida (edited by Professor Krista Williams)

Nadia-humpback whale 3Have you ever imagined that a whale could hug you? It sounds impossible, but the humpback whale’s large pectoral fins would allow it to likely embrace not only you, but also your entire house! The humpback whale (Megaptera novaengliae) is the fourth largest whale in the world. It is distributed throughout all the oceans. Due to its large amounts of fat, was hunted intensely until almost going extinct. By data such as its amazing morphology and peculiar behavior, the humpback whale is one of the most interesting marine mammals.

The Megaptera novaengliae whale is the fourth largest whale in the world (Frisch-Jordan 2014) commonly referred to as “humpback whale”, because when diving, it arches its back sharply showing its prominent dorsal fin, generating the impression of a hump (Frisch-Jordán 2014). It is characterized by have long pectoral fins, which can measure up to a quarter of the total length of its body (Guerrero-Ruíz et al. 2006, Niño-Torres et al., 2011, Frisch-Jordán 2014). Its dorsal coloration is black, while the ventral can vary in shades ranging from black to white (Niño-Torres et al., 2011). They get to measure from 13 m to 18 m and weigh 30 t to 40 t, the females being larger than males (Guerrero-Ruíz et al., 2006; Niño-Torres et al., 2011). By such dimensions it is considered to be one of the largest animals in the entire ocean.

The humpback whale distribution is influenced by the seasons of the year: in autumn and winter it is distributed in tropical and subtropical waters, where baby whales grow and adult whales breed; while in spring and summer they inhabit zones of temperate-cold climate where they feed (Guerrero-Ruíz et al., 2006; Niño-Torres et al., 2011; Frisch-Jordán, 2014). In Mexico they are seen in the Peninsula of California to the coast of Chiapas at the beginning of December until the end of April (Niño-Torres et al., 2011), where, as mentioned, in this area the breeding and reproduction is carried out. The breeding is carried out only by the females and the baby whales remains at their side until 11 months. In terms of reproduction, males perform vocalizations called songs to attract females (Guerrero-Ruíz et al., 2006). This way of life is perhaps the one that has helped them to dominate the oceanic waters until today.

These whales possess large amounts of fat and were therefore hunted intensely, which caused their population to decrease drastically (Urbán & Aguayo 1987, Guerrero-Ruíz et al. 2006, IWC 2018). As a consequence, the International Whaling Commission in 1995 prohibited its commercial capture (Guerrero-Ruíz et al 2006, IWC 2018). In Mexico, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) catalogs humpback whales in Appendix I (CITES 2016), while under the standards it is under special protection in NOM-059-SEMARNAT-2010 (DOF 2010), and in NOM-131-SEMARNAT-2010, in addition to an agreement that establishes a refuge area of protection for large whales the marine areas that are part of the national territory (DOF 2002). As a result of these rules and laws of protection, it has been possible to preserve the species of humpback whale.

In conclusion, the humpback whale is unique because of its large size and is an important species for being the only one that has such large pectoral fins, in addition to its behavior and strategies that have allowed it to dominate the oceans. The preservation of this species has been made possible with the help of laws and norms generated for their protection. We believe that it is important for these organisms to continue being studied in order to contribute more to their conservation until their total population recovery is achieved.

References:

CITES. Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres. Apéndices I, II Y III. Consultado el 14 de enero de 2019: https://cites.org/esp/app/appendices.php

DOF. Diario Oficial de la Federación. 2002. Acuerdo de área de refugio para proteger grandes ballenas de los subórdenes Mysticeti y Odontoceti. Secretaría de medio ambiente y recursos naturales. Consultado el 14 de enero de 2019: http://dof.gob.mx/nota_detalle.php?codigo=733639&fecha= 24%2F05%2F2002

DOF. Diario Oficial de la Federación. 2010. Norma Oficial Mexicana NOM-059-SEMARNAT-2010, Protección ambiental-especies nativas de México de flora y fauna silvestre-Categorías de riesgo y especificaciones para su inclusión, exclusión o cambio-Lista de especies en riesgo. Secretaría de medio ambiente y recursos naturales. Consultado el 14 de enero de 2019: http://www.profepa.gob.mx/innovaportal/file/435/1/NOM_059_SEMARNAT_2010.pdf

DOF. Diario Oficial de la Federación. 2011. Norma Oficial Mexicana NOM-131-SEMARNAT-2010, Lineamientos y especificaciones para el desarrollo de actividades de observación de ballenas, relativas a su protección y la conservación de su hábitat. Secretaría de medio ambiente y recursos naturales. Consultado el 14 de enero de 2018: http://www.dof.gob.mx /nota_detalle.php?codigo=5214459&fecha=17/10/2011

Frisch-Jordán A. 2014. Capítulo 9. Siguiendo a las ballenas jorobadas: catálogo de fotoidentificacion FIBB. Pp: 172-189 In: Cifuentes-Lemus J. L. & F. B. Cupul-Magaña. Temas sobre investigaciones costeras. Universidad de Guadalajara, México.

Guerrero-Ruíz, M., J. U. Urbán-Ramírez & L. Rojas-Bracho. 2006. Las Ballenas del Golfo de California. Instituto Nacional de Ecología (INE-SEMARNAT), México 524 pp.

IWC. International Whaling Commission. 2018. A brief of the ‘Status’ of whale populations, International Whaling Commission. Consultado el 14 de enero de 2019: https://iwc.int/status.

Niño-Torres, C.A., J. Urbán-Ramírez & O. Vidal. 2011. Mamíferos Marinos del Golfo de California: Guía ilustrada. Publicación especial No. 2, Alianza WWF México-Telcel. 192 pp.

Reilly, S. B., J. L. Bannister, P. B. Best, M. Brown, R.L. Brownell Jr, D. S Butterworth, P. J. Ckapham, J. Cooke, G. P. Donovan, J. Urbán & A.N. Zerbini. 2008. Megaptera novaeangliae. The IUCN Red List of Threatened Species 2008. Consultado el 14 de enero de 2019: http://www.iucnredlist.org/details/ 13006/0.

Urbán, J. & A. Aguayo. 1987. Spatial and seasonal distribution of the humpback whale, Megaptera novaeangliae, in the mexican Pacific. Marine Mammal Science 3(4): 333-344.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.