Gervais’ beaked whale (aka the Gulf Stream beaked whale or Antillean) is a toothed whale that belongs to the cetacean species, which is comprised of whales, dolphins and porpoises and includes over 85 known species of cetacea.
Among the beaked whale family Gervais’ beaked whale makes up one of over 20 recorded species of beaked whale.
This whale recieved its name from a French scientist named Paul Gervais who first identified the species in 1855.
For several decades following this observation no other specimen were found which led many individuals to doubt this marine mammal was a newly identified species until another whale was captured in 1889 and later in 1905.
As previous observations suggests Gervais’ beaked whale is rarely spotted/identified whale that is typically found living in tropical/sub-tropical climates in the central and north Atlantic oceans.
As the name suggest these whales are named by their beak shaped skulls and close relationship to other beaked whales within their family.
Due to their rare status collecting information on this species has proven to be challenging.
Much of the information that has been gathered about the Gervais’ beaked whale has been collected from research done on stranded whales.
Physical Characteristics and Appearance
When fully matured these whales measure in at between 15 – 20 ft. long and weigh between 2,500 – 3,300 lbs. with females growing slightly larger than their male counterparts.
They have a small tapered head with a long beak compared to other whale species and a small dorsal fin which is located down the far side of its back.
The flippers are fairly small in size and are used for swimming and turning in the ocean and the rear flukes are tapered back to minimize water resistance while helping the whale propel itself through the water.
When swimming these marine mammals may fit their flippers into depression pockets to minimize drag as they move forward through the ocean.
Although Gervais’ beaked whale is a toothed whale males appear to have only two visible teeth while the females teeth are hidden.
In terms of color these whales tend to either be a dark gray to black or bluish color on their upper body, which is believed to darken as they age.
The lower body is a lighter shade of gray and female whales may have light spots around the face and genitals.
They may also have dark circles around their eyes.
Diet and Hunting Methods
These marine mammals are known to eat a diet consisting of squid, shrimp, octopus and fish.
Echolocation may be used to help Gervais’ beaked whale locate food and navigate at the ocean night or when hunting in deep dark waters.
During extended dives these whales have been observed holding their breath for up to an hour before resurfacing for air.
Nothing is known about the hunting methods these marine mammals use to capture their prey, however it is likely that they swallow their food whole as their teeth appear to have little to no functional use.
Habitat and Migration
Gervais’ beaked whales tend to prefer living in warmer tropical climates in deep waters throughout the central and northern Atlantic ocean.
While spotting these whales has been difficult they have been spotted in places such as Africa, Brazil, the Canary Islands, the Gulf of Mexico, Ireland and in warmer areas of the United States.
Given their small range and distribution when compared to other whale species these marine mammals appear to either be non migratory
It is believed that these whales have always been a rare species, so spotting them and gathering research has been extremely tough for researchers and marine biologists.
Social Structure and Communication
Not much information is known about this species social structure.
Current research assumes that these whales tend to prefer swimming in small groups that may include two or more whales.
During mating periods male whales may be particularly aggressive towards one another as scarring has been observed on the bodies of stranded male beaked whales.
This scarring resembles potential markings from the teeth of other male whales in addition to possible markings made by sharks such as the cookie cutter shark.
From limited observations of these whales they have been observed breaching the water and taking extended dives after short periods of surfacing.
Long dives have been reported as lasting nearly hour followed by a short surfacing to obtain fresh air and a repeat dive.
Reproduction and Lifespan
Female whales are believed to reach sexual maturity when they reach 14 – 17 ft. and both sexes are estimated to have a lifespan of 25 – 50 years depending on their health and the threats they face in the ocean.
As with other species female whales feed their young with a thick paste like milk that they produce from the glands until their young is able to hunt and survive on its own.
While the gestation period for Gervais beaked whale is unkown the estimates of other beaked whales range from 12 – 17 months depending on the species.
Threats
Gervais’ beaked whale has been known to be caught in fishing nets and other fishing gear, however these cases are rare as finding these marine mammals has proven difficult for researchers and marine biologists.
Other threats may include noise pollution which is created by sonar, loud jet engines, explosives and other noisy equipment.
These types of sounds may cause interference with the whales ability to use echolocation, navigate the ocean, locate food and communicate with others whales.
Other beaked whale species have been observed dealing with mass strandings during extensive sonar use which is believed to cause possible brain trauma or disorientation.
In regards to their endangerment status these marine mammals are listed as data deficient due to a lack of data on overall population sizes.
Predators
Potential natural predators among this species is unknown, however Gervais beaked whale may occasionally be attacked by large sharks.
Distinctive scars and markings have been found on the bodies of beached/stranded whales which suggests that they may have been caused by sharks and other potential predators.