A Mother–Calf Humpback Whale (Megaptera novaeangliae) Pair from the Southeast Pacific Population Sighted in Mexican Waters

The humpback whale (Megaptera novaean-gliae) is a species with cosmopolitan distribution (Clapham & Mead, 1999); within the large population of the North Pacific Ocean, five Distinct Population Segments (DPSs) have been recognized (Bettridge et al., 2015). Individuals belonging to at least two DPSs (Mexican and Central American) feed from Alaska to California in June through October and then migrate to the coastal waters of Mexico and Central America in October through May to breed (Acevedo & Smultea, 1995; Urbán et al., 2000; Calambokidis et al., 2001, 2008; Alava et al., 2012; Bettridge et al., 2015; Figure 1). Meanwhile, humpback whales from the Southeast Pacific (SEP) DPS feed in waters off southern Chile and Patagonia and in waters surrounding the Antarctic Peninsula; they arrive at breeding grounds between May and December in coastal waters from Peru to Costa Rica (International Whaling Commission [IWC], 1998; Scheidat et al., 2000; Alava et al., 2012; Bettridge et al., 2015; Acevedo et al., 2017; Avila et al., 2020; Figure 1). Therefore, Central American coastal waters represent the potential range limit for different humpback populations/DPSs and correspond to an overlapping region for humpback whales distributed in the Northeast Pacific (NEP) and SEP (Acevedo & Smultea, 1995; Flórez-González et al., 1998; Calambokidis et al., 2001, 2008; Bettridge et al., 2015; Guzmán et al., 2015; Acevedo et al., 2017; Figure 1). However,individual whales can disperse beyond these “recognized” wintering ranges—for example, at least 33 humpback whale sightings were recorded between 2015 and 2018 in Nicaraguan waters belonging to the SEP, including some individuals observed in Antarctic feeding grounds (De Weerdt et al., 2020).