Biologists carry out meticulous mission to save aggressive hunter.
Endangered Sawfish Takes Amazing Road Trip From Sweden to Spain
VALENCIA, Spain— — A rare largetooth sawfish traveled 1,738 miles in 60 hours in a truck to a new aquatic home, thanks to cutting-edge technology. The goal is to protect the endangered species.
Pristis Pristis is considered a critically endangered species by the Red List of the International Union for Conservation of Nature (IUCN). Population growth is slow — a litter produces seven to nine pups. The species is difficult to find and monitor in its natural habitat in tropical and subtropical coastal waters worldwide.
The adult predator fish can grow up to 25 feet in length and weigh as much as 1,300 pounds, presenting a challenge for the transport team.
The plan involved more than 30 experts including vets, aquarists, biologists and transport teams in a highly coordinated effort.
Carla arrived at the Oceanografic in Valencia on June 19, 2019. However, the trip was revealed to the public by the Oceanografic only on International Sawfish Day, Oct. 17, after a tense four months in which she acclimatized to her new home.
“Plans for the transfer started a year ago, as the Swedish aquarium was becoming too small for the fish. Oceanografic offered to give it the space it needed,” said Carlos Taura, biologist assistant of the Oceanografic.
There were three critical challenges during the transport operation: catching the animal in the Swedish aquarium, transporting it to Spain, and finally transferring it to the Oceanografic. The animal was moved from the truck’s technical gallery, as it is called by keepers, to the main tank, which is about 330 feet apart.
“We needed to choreograph everyone around the tanks and use a fork-lift to move the animal from the lorry (truck) to the tank,” Taura said.
Carla was measured on arrival in Valencia and samples were taken to check on her health. She was found to be calm and healthy. Then, the doors of the 18 million-gallon ocean tank at Oceanografic were opened and divers guided Carla in and monitored her until she found the bottom.
A cover on her nose was removed, and Carla started moving and swimming after 20 minutes, to the delight of the team.
Carla adapted well to the tank, but keepers were anxious about whether she would eat. Keepers used different kinds of fish — frozen and fresh — to tempt her. Carla finally chose a Mediterranean fish, a mullet, that had been caught by the keepers.
Since then, Carla has been consuming a varied diet — large pieces of hake, mackerel, cod, jack, European flying squid, salmon, tuna and mullet.
She has adapted well over the past few months and even has a friend, Mr. Jasson, a male longcomb sawfish (Pristis zijsron). But since the two are different species, they won’t mate.
Carla is nocturnal and prefers to stay in the bottom of the tank, but is constantly alert to threats. She uses her hypersensitive nose to detect the movement and even the heartbeat of buried prey.
“She is a very active animal, more so than Mr. Jasson and is a very aggressive hunter. She swims a lot and is often seen moving around different parts of the tank,” said Taura. “Other fish tend not to approach to her as she is pretty big and has a big mouth filled with teeth that keeps them away.”
The team at Oceanografic are hoping the middle-aged swordfish will find a male to breed with, but Taura warns “it will not be so easy. The possibility of having an aquarium willing to take its animals out is not very common.”
Longtooth sawfish have suffered from overfishing in the wild. They are sought after for shark finning and the novelty of their saw, which gets entangled in nets. There is also the illegal international trade in its parts, including skin, rostrums, organs and teeth.
Australia is the only country with a healthy population of the once-global species. It is protected in more than 10 countries. Conservation efforts are taking place in Australia and the U.S.
(Edited by Fern Siegel and Matthew Hall)