NOT SUCH A WHALE OF A TIME

The past few months have been busy ones for Station 34 (Yzerfontein) with several callouts for whale disentanglements. By Cherelle Leong

THE WEST COAST of South Africa is home to a wealth of marine wildlife, and this past summer saw the relatively rare occurrence of a superpod of humpback whales. The pod of up to 200 individuals was seen just off Cape Town’s Atlantic beaches from Camps Bay to Scarborough. Marine biologists believe this unusual congregation is due to a combination of plankton blooms and other ocean conditions. A few years back the decline in whale numbers had been cause for concern, but seeing this many animals signals that humpback whale populations are recovering, which is exceptionally good news.

For Station 34 (Yzerfontein), it was a busier-than-usual season for whale disentanglement calls. These cases peaked in the first week of February, when the station managed three disentanglements in only four days and another a week later.

The first call came in on 1 February at 08h15 from a trawler just south of Dassen Island. Station commander Andre Livingstone-Louw placed Station 34 crew on standby while waiting for a member of SAWDN from Cape Town to join the operation. Thirty minutes after launching, they located the 8m juvenile humpback whale, which appeared to be anchored to the seabed, presumably by a rope wrapped around its caudal peduncle (the tapered region between the dorsal and tail fins). When a second whale appeared close to some surface buoys nearby, the crew initially thought it may also be entangled, but were soon able to confirm this wasn’t the case once it was observed diving and swimming away.

The entangled whale, on the other hand, couldn’t raise its tail and wasn’t spending much time at the surface. To complicate matters, the water was so murky, the crew couldn’t make out the configuration of the ropes and buoys. Working alongside a distressed giant was hard enough without having to guess which lines to cut where. A grappling hook was used to hook the line below the buoy and pull the rescue vessel closer so that a kegging buoy could be attached to prevent the whale from diving deeper. Using the lines, several unsuccessful attempts were made to pull the whale’s tail closer to the surface so that the line could be cut free. Before they could try again, the crew had to divert to evacuate a patient from a vessel and the disentanglement operation was put on hold temporarily.

Returning later, the crew found the whale still entangled but the kegging buoy gone. The whale was also even more agitated and slapped the water with its tail when the rescuers attempted to pull up the line to cut it. It was going to require patience and some careful manoeuvring to get the whale free. The trailing line was first cut shorter to prevent further entanglement. Then two more cuts were made, one close to the left flipper, which brought the tail closer to the surface, and finally a cut could be made close to the caudal peduncle, allowing the whale to swim free.

A whale disentanglement is a timeconsuming task, requiring patience and skill.

AT 07H35 ON 2 FEBRUARY, the same trawler called in reports of two more whale entanglements in a similar location, roughly three nautical miles apart. Station 34 put out a call for assistance from the other stations in Cape Town, as some of their crew members couldn’t take a second day off work. Crew responded from NSRI Head Office and Station 18 (Melkbosstrand). Arriving at the coordinates that had been given, they were unable to locate any whales. A circular search was initiated, starting from the point where the second whale was last seen. Forty minutes later, a 9.5m juvenile humpback whale was located. It had lines wrapped around its body, behind the dorsal fin, and through its mouth.

While the lines anchored the whale to the seabed, they were long enough to enable the whale to dive and swim in a large circle, so it would disappear for two to five minutes at a time. This made for a very challenging disentanglement operation. Two kegging buoys were attached to the line at 30m and 5m from the knotted lines. But every time the vessel came close enough to cut the line, the whale would get agitated and try swim away. There was no choice but to back off and wait until the whale relaxed enough for another approach. It was more than an hour after arriving at the scene that the volunteers were finally able to cut the line near the animal’s mouth. As the vessel repositioned for a second cut, crew members noticed that the whale had managed to free itself from the rest of the entanglement, and it wasted no time disappearing into the big blue.

Knowing there was another entangled whale out there, the Yzerfontein crew launched a search the following day, 3 February, but no whale could be found. Then on Monday 7 February another call came in of a whale caught in the lines southwest of Dassen Island. Station 18 responded to assist Station 34 once more, this time joined by Station 4 (Mykonos). Arriving on the scene, they found an exhausted 7.5m juvenile humpback pinned down by lines wrapped around its tail and through its mouth. Two kegging buoys were attached, but as the first cut was made to the left of the whale, it dived, snapping both kegging buoy lines in the process. Even when the whale resurfaced, poor water visibility was making it difficult to locate and cut the line wrapped around the tail. Several attempts were made to lift the tail section closer to the surface, but no such luck. A call was made to the trawler to come and assist. While waiting for them to arrive, the volunteers made a last-ditch attempt to lift the tail line close enough to the surface to make a quick cut. This time the cut was successful, yet the whale remained motionless for a while. Then, with a sudden quick movement, it swam free.

For the crew this was an emotional moment. The entire operation had taken almost three hours to complete. To see a whale exhausted, frustrated and trapped is hard, but being able to help cut it free is indescribable. No matter how many disentanglements NSRI and SAWDN complete, each one remains memorable.