The species identification of whales, dolphins and porpoises at sea remains challenging, particularly for cryptic species like beaked whales (Family: Ziphiidae). Here we use environmental (e)DNA for identification of Sato’s beaked whale, Berardius minimus , at sea. This species was first described in 2019 and, to date, all but one genetic sample has been collected from beachcast carcasses. Sato’s beaked whales are difficult to...

Introduction Estimating the genetic diversity of cetaceans at sea, particularly abundant social delphinids, can be difficult with traditional biopsy sampling of individuals. Environmental DNA (eDNA) metabarcoding has been shown to be a powerful tool for the identification of species assemblages and estimation of genetic diversity, especially in aquatic environments. Methods We collected 126 samples of seawater from within the...

In 2024, an expedition was conducted off northwestern Baja California, México, to find and identify the beaked whale species that produced the BW43 echolocation pulse previously recorded in this area and elsewhere in the North Pacific. There were five Mesoplodon sightings and 21 BW43 acoustic detections on both a towed array and drifting pole buoy recorders over the course of the survey. Three of the sightings had concurrent a...

Although Hubbs' beaked whale ( Mesoplodon carlhubbsi ) was previously known from over 60 strandings on both sides of the North Pacific, it had been identified alive in the wild only once, off Oregon in 1994. In September 2021, we conducted a search effort for beaked whales off the coast of Oregon using a towed hydrophone array and a visual search team. Approximately 350 km off the Columbia River mouth, we detected the vocaliza...

The krill surplus hypothesis of unlimited prey resources available for Antarctic predators due to commercial whaling in the 20th century has remained largely untested since the 1970s. Rapid warming of the Western Antarctic Peninsula (WAP) over the past 50 years has resulted in decreased seasonal ice cover and a reduction of krill. The latter is being exacerbated by a commercial krill fishery in the region. Despite this, humpba...

Commerson’s dolphins ( Cephalorhynchus commersonii ) are separated into the subspecies C. c. commersonii , found along southern South America (SA) and the Falkland Islands/Islas Malvinas (FI/IM), and C. c. kerguelenensis , restricted to the subantarctic Kerguelen Islands (KI). Following the dispersal model proposed for the genus, the latter is thought to have originated from SA after a long-distance dispersal event. To evaluat...

Humpback whales wintering in tropical waters along the Atlantic and Pacific coasts of the South American continent are thought to represent distinct populations or “stocks.” Here we present the first analysis of genetic differentiation and estimates of gene flow between these breeding stocks, based on both mitochondrial DNA (mt DNA ) control region sequences (465 bp) and 16 microsatellite loci from samples collected off Brazil...

The interplay of natural selection and genetic drift, influenced by geographic isolation, mating systems and population size, determines patterns of genetic diversity within species. The sperm whale provides an interesting example of a long‐lived species with few geographic barriers to dispersal. Worldwide mt DNA diversity is relatively low, but highly structured among geographic regions and social groups, attributed to female...

We present genetic and morphological evidence supporting the recognition of a previously synonymized species of Mesoplodon beaked whale in the tropical Indo‐Pacific, Mesoplodon hotaula . Although the new species is closely‐related to the rare ginkgo‐toothed beaked whale M. ginkgodens, we show that these two lineages can be differentiated by maternally (mitochondrial DNA ), biparentally (autosomal), and paternally (Y chromosome...

Humpback whales undertake long‐distance seasonal migrations between low latitude winter breeding grounds and high latitude summer feeding grounds. We report the first in‐depth population genetic study of the humpback whales that migrate to separate winter breeding grounds along the northwestern and northeastern coasts of Australia, but overlap on summer feeding grounds around Antarctica. Weak but significant differentiation be...

Historically, the range of the southern right whale ( SRW ) included winter calving grounds around the North and South Islands (mainland) of New Zealand ( NZ ) and in the NZ subantarctic Auckland and Campbell Islands. Due to extensive whaling in the 19th and 20th centuries, no SRW was seen around mainland NZ for nearly four decades (1928–1963). Here we present evidence for the regular use of the mainland NZ wintering ground, p...

The identification and characterization of reproductively isolated subpopulations or ‘stocks’ are essential for effective conservation and management decisions. This can be difficult in vagile marine species like marine mammals. We used paternity assignment and ‘gametic recapture’ to examine the reproductive autonomy of southern right whales ( Eubalaena australis ) on their New Zealand (NZ) calving grounds. We derived DNA prof...