Early whale season in Primeiras and Segundas Archipelago
By Jean-Baptiste Deffontaines, Natural Resource Management Intern, P&S Program
Earlier this April, while the Natural Resource Management (NRM) Team of the P&S Program were planning activities for the next quarter, the Marine NRM Officer received a phone call from the head community ranger who just received news from rangers posted on “Ilha de Mafamede”, the northern-most island of the Segundas archipelago off of Angoche: “We have a beached whale!”
April is not the season for observing whales in the Mozambican channel and so the news came as a surprise with many of us wondering what species it could be. Humpback whales, the most common whale found in the channel, migrate through between July and October during the breeding season. Even during season, it is extremely rare to hear of mortalities, whales washing ashore or beaching themselves.
As the ‘supposed’ whale was dead, questions concerning its disposal were raised. The ranger requested the teamto bring hoes to bury it… hoes to bury tons and tons? “Perhaps it is a dolphin?” the team surmised. In any case, a visit to the island to follow up on the information reported and identify the species was needed. The team disembarked on the Navy´s only functioning boat the following morning, accompanied by a technician from IIP (Fishing Investigation Institute), the governmental institution legally able to identify the species.
Indeed, upon arrival, the ´whale´ appeared to be a huge dolphin. Yet upon closer examination, the team was led to a different conclusion.
Based on the carcass´ condition, the death had occurred a long time ago, perhaps far out in the ocean. The meat was already putrefying and gave off a powerful odor. The back-end of the body was hacked and slashed, due to a suspected collision with a boat offshore, one theory proposed. Unfortunately, all evidence of the tail fluke was lost, but the team was able to observe the dorsal and right pectoral flippers.
Although the animal was at a rather late stage of decay than ideal for species identification, the team conducted an examination and noted important distinctions. The impressive size of the animal, proportions and distances measured between features confirmed the hypothesis that it was not in fact a dolphin. The important shifting between pectoral and dorsal flippers, the bulging eyes and head, particularly short mouth compared to the rest of the body, and dolphin-like beak led the team to conclude:
A Beaked whale! What an interesting and unusual discovery! (It could have been better alive but at least it’s really interesting from a scientific point of view…)
Which species? Really hard to say… Only measurements of the skull will allow the identification of the species. The body will be buried on the island. Maybe in a few months the skull can be unearthed after complete degradation of the soft tissues.
Not much is known about beaked whales. Twenty-one species have been identified, few by sight, some by formal description.
Still others are known only from remains. (Only three to four species are considered reasonably well-known and documented. Furthermore, individual species are also very difficult to identify as body form varies only slightly from one species to another.
Although information can be obtained from beached whales such as with the specimen found, in Mozambique there is limited knowledge and few resources available for their identification and study. Most beached whales are buried or wash back to sea without interest or identification. On account of additional factors such as the civil war and political instability, Mozambique was left virtually unexplored for decades. Demonstration: If you were to take a minute and open your favorite biology book (Fishes, Birds, Mammals, Bacteria, etc.), you may not find much about Mozambique. This may lead you to assume that it is not a very biodiverse country. Untrue! The lack of information on biodiversity in Mozambique simply means that there is more out there to discover!
Little information on beaked whale biology available and a lack of current research presents a slim but possible chance: Could it be a new species?