New insight into Monk Seal evolutionary history, the plight of the Maui's dolphin and successful disentanglement of humpback juvenile off California Coast

By Lauren Campbell, Conservation Manager

Monk seals represent one of the most critically endangered group of marine animals in the world. Of the three species of monk seals, only two, the Hawaiian and Mediterranean species are still in existence.  The Caribbean monk seal was confirmed extinct in 2008.  While scientists have classified all three species under a single grouping, a new study suggests that this classification may need to be reevaluated.

Currently, all three species are classified under one genus, Monachus.  After reviewing genetic and anatomical evidence, however, researchers have concluded that the Caribbean and Hawaiian species are so genetically and morphologically distinct from the Mediterranean species that the creation of a new genus, Neomonachus, may be warranted. 

The Caribbean and Hawaiian species, also known as the “New World” species, separated from the Mediterranean species over 6 million years ago.  The Caribbean and Hawaiian species themselves split about 3-4 million years ago when the Isthmus of Panama closed and separated the Atlantic and Pacific Oceans.  Today, only about 1,200 Hawaiian monk seals and 600 Mediterranean monk seals are left in existence. 

If a new genus is adopted, it would mean that both the Mediterranean and Hawaiian monk seals are the sole representatives of a genus, a move that has huge conservation implications.  A new genus would also be momentous considering that it has been over 140 years since scientists have described a new genus in the pinniped family.   

Monk seals are not the only marine species facing an unpromising future.  Half way around the world, the serious plight of the Maui’s dolphin is being highlighted at the annual International Whaling Commission scientific meeting.  New research confirms that the dolphin species could face extinction by 2031.

Named after the Maori indigenous name for the North Island, Te Ika a Maui, the Maui’s dolphin is a sub-species of Hector’s dolphin and one of the rarest dolphins in the world.  Found only along the west coast of New Zealand’s North Island, the population is estimated at a mere 55 individuals and less than 15 breeding females. 

The slow breeding rate and small population size of the Maui’s dolphin has made the species especially susceptible to extinction.  The dolphin is vulnerable to set net (gill net) and trawl fishing, marine pollution and debris, boat strikes and genetic bottleneck.  While set nets are banned in over 6,000 sq. km. of the dolphin’s range, conservation groups  advocate for complete fisheries closures and a prohibition on the use of all gill and trawl nets.  To urge the New Zealand government to take stronger and more immediate actions to save the Maui’s dolphin, please sign the online petition!

With all the disheartening news surrounding marine mammals in the past week, it is exciting to highlight some good news!  Last week, a juvenile humpback whale was freed from a life-threatening entanglement in fishing gear off the coast of California.

The whale was first spotted on April 27th in Monterey Bay with its tail tangled in a crab pot line.  The response team was able to assess the whale and attach a satellite tag, and the following day removed both the crab pot and about 250 feet of line,   

In the days following, the whale was unable to rid itself of the remaining line.  Fortunately, due to the attached transmitter, response crews were able to continually monitor the whale’s position as it traveled along the California coast.  On

Wednesday, May 14th, the whale was pinpointed about 5 miles off the Santa Barbara coast.  Once responders reached the whale, they noticed that the remaining crab pot line was wrapped and knotted around the whale’s tail.  The knot was so tight that it had cut several inches into the animal’s blubber and tissue.  Crews were able to snag the ends of the line and cut the knot loose, freeing the animal completely. 

On May 1st, another humpback was spotted entangled in a crab pot near Monterey Bay, but disappeared before it could be marked with a tracking buoy.  In Hawai‘i, a total of 17 different humpbacks were reported entangled during the recent winter breeding season (November-May).  Of those, 4 were officially disentangled by response teams.  An estimated 300,000 dolphins and whales die each year as a result of entanglement in fishing gear.