Humpback whales in Banderas Bay, Mexico: relative abundance and temporal patterns between 2004 and 2017 (original) (raw)

2021, Latin American Journal of Aquatic Mammals

population parameters of humpback whales in breeding areas to improve management practices. This study also highlights the potential of opportunistic platforms, such as whale watching tour boats, as viable sources of quality information, particularly in contexts when funding is limited. a result. Between 2004 to 2006, project "SPLASH: Structure of Populations, Levels of Abundance and Status of Humpback Whales" (Calambokidis et al., 2008) assessed several parameters of the North Pacific population of humpback whale. SPLASH results reported a yearly population increase of 6.8% and an estimate of 21,808 whales in the whole North Pacific, a number that surpassed pre-whaling population estimates (Barlow et al., 2011). The findings of Calambokidis et al. (2008) from the SPLASH project suggested that the Mexican Pacific was the second most important breeding region for humpback whales of the North Pacific (after the Hawaiian Archipelago), receiving about 40% of wintering humpback whale annually. Medrano et al. (2007) reported that humpback whale population abundance in Banderas Bay was 15 times greater than in the surrounding waters of the Eastern Tropical Pacific and the entrance to the Gulf of California. Later, Martinez-Aguilar (2011) assessed the population abundance of humpback whale in wintering areas of the North Pacific, particularly in Mexican waters (i.e. Baja California, mainland and Revillagigedo) and reported a higher recovery rate for humpback whales wintering in Mexico compared to those wintering in Hawaii. Humpback whale population increases are directly related to oceanographic conditions such as thermal fronts (impacted by climate change) and to El Niño-Southern Oscillations (ENSO) in high latitude summer feeding areas that either directly or indirectly affect prey and habitat availability and therefore, reproductive success (Salvadeo, et al.