El océano menos recorrido

Cada mamífero marino varado es un tesoro oculto de información científica que proporciona datos de otra forma inobtenibles sobre la salud de las poblaciones de delfines salvajes. Una necropsia ayuda a determinar la causa de muerte y datos históricos de vida.

La vida de una veterinaria de mamíferos marinos.

SI HABLAS CON CUALQUIER PERSONA DE MENOS DE 13 AÑOS, and they have probably been asked, “What do you want to be when you grow up?” I was just 3 years old when I knew I wanted to be a veterinarian. Growing up on coasts — first Cape Cod, Massachusetts, and then Southeast Florida — I was practically raised by the Atlantic Ocean’s starfish, seahorses, sea turtle hatchlings, and so many other ocean creatures that have been my friends and confidants. I have since dedicated my life to conserving, protecting, and loving these animals. As there are few guidebooks on caring for sea creatures, my decades-long journey as a marine mammal veterinarian has been far from ordinary. 

The ocean’s soothing sounds can easily lull us into serenity, but a community in dire need of conservation, research, and protection lies below the surface. The ocean’s health is in crisis, and marine mammals are the proverbial canary in the coal mine. I have traveled the world to work with a variety of marine mammals. The following are some highlights and examples of the many species, situations, and places I have been called to assess, care for, and treat marine mammals.

Los manatíes, que están relacionados con los elefantes, se ven afectados por una multitud de amenazas humanas, incluso golpes de embarcaciones, enredos en sedales de pesca y una destrucción del hábitat. El Servicio de Parques Nacionales y Estudios Geológicos de Estados Unidos (U.S. Geological Survey and National Park Service) ayuda a conservar esta especie amenazada mediante su etiquetado y monitoreo durante evaluaciones de salud anuales.

Esta foca de casco, suavemente sujetada mientras recibe un tratamiento para salvar su vida, se recuperó por completo y fue liberada en sus aguas nativas en el Atlántico Norte.

UNA HISTORIA DE DOS CACHALOTES

We are used to swimming with numerous species of tropical fish, sharks, and dolphins while working and playing in the Florida Keys’ turquoise waters. A few miles offshore, however, the Gulf Stream serves as a highway for a large variety of pelagic species that travel immense distances, including sperm whales. Until recently, Moby-Dick was my best knowledge of these leviathans.

A lo largo de los últimos 20 años no se registraron varamientos de cachalotes en los Cayos de la Florida, por lo que me sorprendió recibir una llamada de un oficial de la Comisión para la Conservación de Peces y Vida Salvaje de la Florida (Florida Fish and Wildlife Conservation Commission, FWC) que me dijo que había una cría de cachalote nadando junto a una embarcación de buceo local. Cuando recibo una llamada para ayudar a un mamífero marino todo lo demás se detiene. Nuestro equipo se trasladó en barco para hacer una evaluación inicial, y encontramos a una cría de cachalote de 3 metros (10 pies) de unos pocos días de vida. La cría se refugió debajo de nuestro buque de investigación mientras dos tiburones tigre del mismo tamaño investigaban su presunta futura comida.

I was in constant touch with my team and warned them to mentally prepare for the harsh reality of witnessing Mother Nature’s food chain. While the circle of life is a reality, watching a distressed baby marine mammal succumb to an agonizing death by large predators is not something veterinary school teaches you to deal with. We observed both sharks making close passes as the baby whale slowly tired and maneuvered closer to shore, where she eventually stranded rather than be eaten alive. As I prepared my medical gear in anticipation of rescue or recovery, my team alerted me that the calf had stopped breathing. It’s never easy to lose a patient, but it can be difficult to see a young life end, especially when it is an endangered species that our ecosystem so desperately needs.

Las enormes mandíbulas de un cachalote macho adulto encallado son impresionantes incluso después de fallecido.

It’s not uncommon for me to have more questions than answers following a postmortem examination. The calf was emaciated, presumably because mom was unavailable to provide nourishment. My only hope was that a microscopic evaluation of each organ collected would provide more compelling answers to what happened and contribute to the limited data we have to help conserve this endangered species. 

Four days later we received reports of a massive whale stranded on an outer reef in the Gulf of Mexico 12 miles north of Key West, Florida. I wondered if it could be the deceased calf’s mother as I raced to the scene with the region’s stranding coordinator, Steve McCulloch, to conduct an evaluation for NOAA Fisheries. Unfortunately, the whale was deceased, and identifying it as an adult male sperm whale proved my theory wrong. To investigate further, I climbed onto the whale to collect skin samples, which can provide a treasure trove of genetic information. Fortunately, resources became available to move the whale to a local marina, where we could conduct a full necropsy the following day. NOAA Fisheries deployed additional staff and resources to collect as much information as possible, and I spent the next 12 hours examining the 47.5-foot-long sperm whale.

Sadly, a small 2.5-pound mass of fishing net was in the whale’s first stomach, which was likely the cause of its demise. Habitat degradation and overfishing have depleted ocean resources to the point where marine species eat anything to satisfy their hunger, with potentially deadly consequences because of our tendency to make oceans our garbage dumps. Worldwide, I find that marine mammal diseases are often the result of compromised environments.

Ingerir 1,1 kilogramos (2,5 libras) de red de pesca fue la causa de muerte de este cachalote de 50 toneladas.

FOCAS DE CASCO EN EL SUR

A typical day in the life of a marine mammal veterinarian does not exist. I have primarily focused my career on marine mammals inhabiting southeastern U.S. waters, and it was unusual to receive a call about two seals on one of Florida’s beaches. Although I doubted that the animals were actually pinnipeds, two Arctic hooded seal pups had somehow found their way to a South Florida beach. Even more unusual was that these two pups appeared to be traveling together because they are usually a solitary species. They do not migrate until they reach sexual maturity, and their usual migratory path does not include South Florida.

We evaluated both seals at our dolphin and whale rehabilitation facility while looking for a more appropriate facility to continue their care and eventually release them. Unfortunately, only one seal survived, and that animal was transported to a New Jersey rehabilitation facility, where it would eventually be returned to the wild. During the postmortem forensic examination, I discovered that plastic spoons, plastic bags, and water bottle labels from all over the world filled the deceased pup’s stomach. As with the sperm whale, I suspect that lack of prey resulted in these wayward seals seeking better locations to satisfy their nutritional needs; the dead pup was eating anything to try and satiate his hunger, which proved fatal.

Mamíferos marinos aprenden a presentarse para exámenes de salud de rutina en centros de cuidado humano.

UN VARAMIENTO MASIVO DE
DELFINES DE DIENTES RUGOSOS

It’s an unwritten rule that if it’s a holiday, there’s an important meeting, or it’s on the eve of a much-awaited dive vacation, a major stranding event is sure to occur. I was attending an out-of-state conference to discuss mass-stranding management when I received a call that a mass stranding of rough-toothed dolphins was taking place in South Florida. Within 30 minutes, I was on a plane.

Después de recibir actualizaciones en tiempo real de que algunos delfines habían quedado varados en la playa, otros estaban rodando en las olas y muchos más estaban deambulando a 27 metros (30 yardas) de la costa, mi equipo y yo consultamos a oficiales de NOAA Fisheries y luego les indicamos a los rescatistas y voluntarios públicos que formaran un cordón humano en el océano para evitar que más delfines se encallaran en la playa con el resto de su manada. Sin embargo, las condiciones meteorológicas se deteriorarían rápidamente, por lo que permanecer en el agua era peligroso.

Poco después, los delfines restantes se encallaron, y cada delfín tenía un voluntario asignado. Me desplacé por la línea para evaluar, tomar muestras y etiquetar a cada delfín. Aún tengo pesadillas sobre este evento; algunos delfines habían perecido y muchos aún estaban en una situación precaria. Tomé la difícil decisión de realizar una eutanasia en muchos de los animales que estaban vivos para aliviar su dolor y su sufrimiento. Solo seis de los 60 animales estaban lo suficientemente saludables como para que nuestro equipo intentara una rehabilitación. Tres de estos delfines sobrevivieron para regresar a su hábitat natural con telemetría satelital que proporcionó datos de conservación fundamentales. 

Como centinelas del océano y la salud de los humanos, los mamíferos marinos son barómetros ambientales vivientes. Compartimos los mismos océanos, comemos los mismos pescados y la humanidad a la larga seguirá los pasos de los delfines.

EL MANATÍ DE FLORIDA

Florida manatees are a keystone species that alerts us to environmental and habitat changes in Florida’s waterways. Weighing more than 2,000 pounds, these gentle giants face innumerable threats to their habitat, including increased boat traffic, entanglement, and ingestion of marine debris. In 2021 a record 1,100 manatees died, which accounted for approximately 12 percent of the state’s population. This year wildlife officials designated Florida manatees as in crisis due to 500 deaths in an unusual mortality event (UME). The designation of a UME puts all manatee first responders, veterinarians, and scientists on high alert and prioritizes research efforts.

I have never observed a manatee without at least one scar from a boat prop. It was no surprise to find out that a manatee in Marathon, Florida, was found with severe boat propeller injuries to the head. It’s hard to imagine that any creature could survive that kind of skull trauma. A prompt rescue response to such a severe injury is critical to increasing the chances of survival. There are limited facilities available to further evaluate and treat manatees, so long transports with intense monitoring are par for the course. Moving and caring for such an enormous animal has numerous challenges, including unpredictable behavior, human safety concerns, and the added pressure of ensuring that patients from a UME arrive alive.

Afortunadamente, este caso tuvo un final feliz. El traslado largo se produjo sin incidentes, y una cirugía posterior para extraer fragmentos de hueso del cráneo le permitió regresar al medio silvestre.

BELUGAS NO TAN PEQUEÑAS

For many people, the popular children’s song “Baby Beluga” is the only familiarity they have with beluga whales, also called sea canaries because of their unique vocalizations. These whales reside far from the warm Florida waters, where I spend most of my time. Like other marine species, beluga whales face numerous environmental threats, such as commercial and recreational fisheries, that compromise their nutritional health. In addition, global warming impacts the water temperatures to which marine mammals and their prey are adapted.

I recently traveled to Norway to examine and evaluate the famed “spy whale” nicknamed Hvaldimir, who arrived in Norwegian waters in 2019 wearing a harness, camera mount, and clips with the words “Equipment St. Petersburg.” No longer in human care, Hvaldimir has learned to forage for live food and now faces the threats of human interactions and living in the waters of a whaling nation. Examining this charismatic animal in below-freezing temperatures was a reminder that extreme environments come with the territory of being a marine mammal veterinarian.

Las muestras recolectadas a partir de necropsias arrojarán información en análisis de laboratorio posteriores.

My work also extends beyond wild marine mammal populations. In prepandemic days I was called to evaluate a beluga whale living in an aquarium facility in China. This whale suffered from an undiagnosable skin condition sampled and studied by the world’s top marine mammal specialists. Working on a whale in managed care can be easier in some respects, especially with animals who volunteer for medical examinations and sampling procedures. Despite exhaustive efforts, however, we could not save this precious life, and that’s always a bad day at the office.

Nevertheless, it’s critical to take the knowledge we gain from both wild and managed-care marine species to preserve, protect, and conserve these vital apex predators that reside in our fragile oceans. AD

© Alert Diver — Q3 2022

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