North Atlantic right whales were once truly North Atlantic with a historic range covering the waters from Florida and West Africa in the south, to the Labrador Sea and across to Norway in the north. Once upon a time, these whales were once common in coastal waters on both sides of “the pond”.
Heavy whaling pressure on these whales almost resulted in their extinction in the 1900’s and as a result, the eastern population is now presumed to be functionally extinct, while the only remaining population of North Atlantic right whales, consisting of fewer than 500 individuals whales and listed as Endangered, are mostly restricted to the coastal waters of United States and Canada.
The sighting therefore, of a right whale off the coast of the Azores (the first in over 60 years) was cause for great celebration but it also raised a lot of interesting questions ….
On the 5th January 2009, Lisa Steiner from Whale Watch Azores was undertaking research with the University of the Azores Department of Oceanography and Fisheries when they sighted, with great disbelief, what they believed to be a north Atlantic right whale. They were able to get good photographs to enable possible identification of the individual whale and promptly sent the images off for comparison with the North Atlantic right whale catalogue. They were thrilled to find that “their” whale, nicknamed Pico after the island near where she was seen, was in fact whale no. 3270.
Whale no. 3270 was an adult female. After her initial sighting in 2002, about 100km east of Cape Cod, she was seen every year (except 2004) in this typical northern habitat of the western north Atlantic population. The last catalogue entry for Pico was the 24th September 2008 when she was spotted in the Bay of Fundy, Canada. Given that she was photographed off the Azores on the 5th January 2009, this tells us that she travelled at least 3,320km in 101 days. However it doesn’t end there, 237 days after her sighting in the Azores, she was resighted back in the Bay of Fundy – so it would appear that her migration to the Azores was all in a year’s work.
Pico appeared to be in good physical condition apart from a healed scarring around the entire tail-stock, evidence that she had fallen victim to the fate of too many other great whales, accidental entanglement in fishing gear.
So what’s going on with Pico?
Long distance movements of right whales are likely motivated by their need to reproduce or to find food. Pico’s diving behaviour and her constant speed and heading, indicated that she was travelling and not foraging when she was observed in the Azores and importantly the preferred food of a right whale was not available at this time of year therefore it is not considered that her reason for being in the Azores was driven by food. Although this is not to say that she didn’t find food elsewhere in offshore waters.
There is of course as the authors of the paper (Lisa Steiner and Monica Silva) note, no reason to believe that the Azores was Pico’s final destination and it is possible that the islands served as a navigational landmark in the middle of the vast ocean. If you were to draw a straight line from the western north Atlantic foraging areas, where Pico was last seen, to the only wintering and possible calving ground known in the northeast Atlantic – Cintra Bay, off the coast of Morocco in the northwest Africa – you’d cut straight through the Azores. So perhaps her extensive travels were driven by reproductive urges?
Pico’s date of birth is unknown but the shape of her head suggests that she was at least two years old in 2002 when she was first sighted and photographed, meaning she would have been over nine years old when she was seen in the Azores. Female north Atlantic right whales are known to reach sexual maturity at an average age of nine years old therefore she could have been sexually mature or close to reaching sexual maturity when she was sighted. It is known that calves are born between December and March, gestation is assumed to last approximately one year and therefore by simple maths, mating must occur where the whales’ winter.
What does this mean for North Atlantic right whales?
Recent DNA analysis of archaeological and museum specimens suggests that what we previously considered to be the “eastern” and the “western” populations of north Atlantic right whales were actually a lot closer genetically than first thought. They were able to show that individuals from different populations would have mixed on either mating and/or feeding grounds and that an individual from the west was as closely related to an individual from the east as it was to one from the west. In addition to this, recent paternity tests conducted on western population calves have shown that the majority have not been fathered by known males from the western population. So where are these elusive eastern males?
Some males are also known to travel out with their known habitat. In 1999, a whale named “Porter” travelled over 5,000km from the coast of Cape Cod to northern Norway where he spent more than one month foraging in the fjords. Less than five months later, Porter was back in the western north Atlantic.
Interestingly, both Pico and Porter were last sighted in 2011. Perhaps they are searching the waters across the Atlantic looking for each other!
The sighting of Pico in the Azores and others made elsewhere suggest that at least some whales may have ranges that extend beyond the coastal waters of north America, to areas where they may be subject to various threats. However, given that WDC together with a coalition of other environmental and animal protection groups are currently suing the US federal government over a failure to take action to protect these whales in their “known” habitat, what chance do they have elsewhere?
With so few individuals remaining, every north Atlantic right whale is precious and immediate steps need to be taken to protect these incredibly vulnerable creatures and ensure their long-term survival.