Sighting of Southern Right Whale Dolphin (Lissodelphis Peronii) in the Magellan Strait, Chile
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Polar Biology https://doi.org/10.1007/s00300-018-02446-4 SHORT NOTE Sighting of southern right whale dolphin (Lissodelphis peronii) in the Magellan Strait, Chile Marco Pinto‑Torres1,2 · Jorge Acevedo3,4 · Carla Mora5 · Eva Iglesias2 · Daniel Bravo2 · Francisco Martínez6 Received: 17 July 2018 / Revised: 22 October 2018 / Accepted: 12 December 2018 © Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract The southern right whale dolphin (Lissodelphis peronii) is a seldom seen cetacean of southern latitudes. In the eastern South Pacifc, there are less than 73 confrmed records of live and stranded animals. Moreover, all live individual records have been sighted in ofshore and deep waters, but not in the shallow water of the channels and fords of southern Chile. Two sightings of southern right whale dolphins were made on March 21 and April 7, 2018 at Ballena Sound and Charles Islands in the western area of Magellan Strait. All individuals were identifed as putative adults. Both sightings may correspond to the same group of animals and, if this assumption is correct, the dolphins would have stayed at least 17 days in the area. Even though it is not clear whether the southern right whale dolphins were initially present in the Magellan Strait, or what route they took from the open sea and what biological and physical properties were determinants for this presence, without a doubt, the occurrence of southern right whale dolphins in the eastern South Pacifc channel systems is unusual. Keywords Southern right whale dolphin · Lissodelphis peronii · Subantarctic ecoregion · Magellan Strait · Chile Introduction a circumpolar distribution in the Southern Hemisphere occurring normally between 30° and 65°S (Brown 1982; The genus Lissodelphis (Gloger, 1841) consists of two Van Waerebeek et al. 1991; Jeferson et al. 1994; Newcomer species of fnless dolphins, the northern right whale dol- et al. 1996). Both species difer in terms of coloration and phin L. borealis (Peale, 1848) occurring normally between habitat, with northern right whale dolphins mostly black 30° and 51°N in the North Pacifc Ocean, and the south- with a white ventral band running from the fuke notch to ern right whale dolphin L. peronii (Lacépède, 1804) with the gular region and observed most in waters with tempera- tures of 8–19 °C (Leatherwood and Walker 1979), while southern right whale dolphins are mostly black dorsally and * Jorge Acevedo white ventrally and inhabit waters with temperatures of 1–20 [email protected]; [email protected] °C (Cruickshank and Brown 1981; Kasamatsu et al. 1988; 1 Programa de Doctorado en Ciencias de La Acuicultura, Newcomer et al. 1996). Universidad Austral de Chile, Los Pinos S/N, Puerto Montt, The distribution of southern right whale dolphins in the Chile eastern South Pacifc has been commonly reported to range 2 Centro FONDAP de Investigación de Ecosistemas Marinos from Arica (18°28′S) to Cape Horn (Fraser 1955; Brown de Altas Latitudes (IDEAL), Universidad Austral de Chile, 1973; Brownell 1974; Aguayo 1975; Van Waerebeek et al. Av. El Bosque 01789, Punta Arenas, Chile 1991; Aguayo-Lobo et al. 1998) with northernmost records 3 Centro de Estudios del Cuaternario de Fuego-Patagonia near Pucusana, Peru (12°30′S) (Van Waerebeek et al. y Antártica (Fundación CEQUA), Avenida España 184, 1991) and the southernmost around 57°S in the Drake Pas- Punta Arenas, Chile sage (Kasamatsu et al. 1990). However, there are less than 4 Programa de Doctorado en Ciencias Marinas y Costeras, 73 confrmed records for all of the eastern South Pacifc Universidad Autónoma de Baja California Sur, Carretera al Sur Km 5.5, 23080 La Paz, BCS, Mexico (Aguayo-Lobo et al. 1998). The normal habitat of southern right whale dolphins 5 Independent Researcher, Carlos Condell 0290, Punta Arenas, Chile appears to be strictly pelagic, though they are sometimes seen nearshore especially where deep water approaches the 6 Fitz Roy Expeditions S.A., Roca 825, Punta Arenas, Chile Vol.:(0123456789)1 3 Polar Biology coast and in upwelling areas (Rose and Payne 1991; Jef- cover (c. 80%). Seventeen days later (April 7, 2018) a second ferson et al. 1994). Of the Chilean coast, the distribution group of fve unusual dolphins was observed near of Charles of southern right whale dolphins is speculated to extend to Island (53°45.60′S, 72°10.05′W) (Fig. 1) located south of at least 170 km ofshore north of 40°S and 250 km of the the MCPA for a time of c. 10 min. The sea during that time southern coast (Van Waerebeek et al. 1991). However, their was fat and slightly cloudy (c. 30%). occurrence inside the channels system has also been veri- Both groups were identifed as southern right whale dol- fed through a few reports of solitary stranded specimens phin based on the combination of unique characteristics such in exterior channels south of 40°S, Magellan Strait and as the pigmentation of a black body with white pigmen- Beagle Channel (Goodall 1978, 1989; Venegas and Sielfeld tation on the melon, rostrum, fanks, pectoral fippers, tail 1978; Gibbons et al. 2000). It has been hypothesized that fukes and ventral surface, and the lack of a dorsal fn (Fraser some individuals enter the channels accidentally or when 1955; Newcome et al. 1996) (Fig. 2). All individuals were unhealthy and become stranded due to the unfamiliar envi- identifed as putative adults and no calves were observed. ronment, which in turn could help explain the skeletal mate- In addition, in both sightings, one dusky dolphin (Lageno- rial found (Van Waerebeek et al. 1991). rhynchus obscurus Gray, 1828) was observed based on the The southern right whale dolphin is listed as Data Def- two-pronged fank patch (Fig. 2). cient by the IUCN Red Data List due to the lack of adequate The behavior of the dolphins on the frst sighting (March information to make an assessment of extinction risk for this 21) was initially swimming at low speed around the vessel species and the scarce knowledge of population structure, during the frst 15 min. Next, they leapt clear of the water among other aspects (Hammond et al. 2012). This species with faster swims and began hitting the sea surface with is also classifed as Data Defcient in the Chilean Species the tail and/or the body. At the same time, swarms of squat National List (RCE 2017). Here, we report the frst occur- lobster (Munida gregaria) were observed on the surface of rence of live southern right whale dolphins in the shallow the water. In the second sighting of Charles Islands (April water of the Magellan Strait, a subantarctic ecoregion of the 7), the dolphins approached the vessel and were bow-riding South Pacifc. for some minutes and then returned to the area where they were initially sighted while the vessel continued its naviga- tion. No squat lobster swarms were seen at the sea surface. Materials and methods There are 41 species of cetaceans described in Chile (Aguayo-Lobo et al. 1998; Acevedo et al. 2006a), of which The sightings were recorded by two of the authors (M. Pinto 17 correspond to the family Delphinidae. A total of 12 dol- and F. Martínez) in the western area of the Magellan Strait phin species have been documented in the fords and chan- onboard M/V ‘Forrest’ in March and April 2018. Non- nels system of the eastern South Pacifc subantarctic ecore- marine mammal scientifc crews were often aboard on that gion (e.g., Aguayo-Lobo et al. 1998; Venegas and Sielfeld trip. These animals were diferent from the usual dolphin 1978; Gibbons et al. 2000; Haro et al. 2015; Acevedo et al. species that inhabit the Fueguian channels, attracting the 2017). Peale’s dolphin (Lagenorhynchus australis Peale, attention of the crew. Photographs and a digital video were 1848) and the Chilean dolphin (Cephalorhynchus eutropia taken of both sightings. The photographs were later reviewed Gray, 1846) are the most typical dolphins inhabiting this by another author (J. Acevedo) with experience in marine ecoregion of Chile (Venegas and Sielfeld 1978; Aguayo- mammal research at Punta Arenas for their identifcation. In Lobo et al. 1998; Gibbons et al. 2000). addition to the photographs and video, a logbook annotation Southern right whale dolphins normally inhabit ofshore was available with time of sightings, group size, behavior, waters, although they are also sometimes seen nearshore, weather and association with another species. especially where deep water approaches the coast (Rose and Payne 1991; Jeferson et al. 1994). To the best of our knowledge, the occurrence of southern right whale dolphins Results and discussion within the fords and channels of the southern tip of east- ern South Pacifc had been documented only through a few On March 21, 2018, during an oceanographic survey in solitary stranded specimens (Venegas and Sielfeld 1978; the Francisco Coloane Marine and Coastal Protected Area Sielfeld 1983; Van Waerebeek et al. 1991; Gibbons et al. (MCPA), a group of fve unusual dolphins was observed 2000). There is also a single reference to a live individual at Ballena Sound (53°39.97′S, 72°23.17′W), north-west of reported in the western area of the Magellan Strait (Gib- Magellan Strait, Chile, in waters with a bottom depth of bons et al. 2000). However, the validity of this sighting can less than 150 m (Fig. 1). The group was observed for c. be questioned because no detail such as date, geographical 30 min (from 16:45 hours). The sea was relatively calm with position and pictures were given. These have also been at sea surface temperature of 8.7 °C, and high level of cloud least ten other confrmed sightings of live southern right 1 3 Polar Biology Fig.