© Copyright Vancouver Aquarium 2014
While on vacation over winter break, my husband made an exciting proclamation. He said: “I’ve decided that I want to be the kind of person who takes tours”. And we are not talking basic museum tour. Think big! Taking an old light-rail train into one of the largest copper mines in Canada on a tour led by a guy who actually worked there in the 50’s (did it!). Soar over Howe Sound with its dramatic mountains and fjords in a seaplane tour (definitely didn’t do it $$$). We decided that the best way to have a fulfilling experience while traveling is to connect with the culture of your destination. But I digress. The most important thing about this new proclamation and dubbing ourselves as “the couple that likes to take tours” is that we spent at day at the Vancouver Aquarium in Vancouver, British Columbia.
I’ve had a minor obsession with Beluga whales since singing along to Raffi’s Baby Beluga on my parent's car cassette player in 1989. The Vancouver aquarium has a mother-pup pair of beluga whales named Aurora and Qita. With questions of acquisition and treatment constantly debated, I have mixed feelings about marine mammals in captivity. But beluga whales live in the Arctic, a place I have not been known to frequent, so we took advantage of the opportunity to view them in captivity. And let me tell you they are the cutest whales ever!!! Who knew that 3,300 pounds of white blubber would be absolutely adorable? Watching beluga melons bounce around like Jello got me to thinking about the purpose for adapting a giant, giggly head. I am sure many of you have been introduced to the concept of echolocation, but I started to wonder about the massive amounts of noise occurring under the ocean surface at any one time. As it turns out, the affects of anthropogenic noise on the behavior of beaked whales such as the beluga has been a recent topic in the news and even in the Supreme Court.
Before we go further, lets take a closer look at the uses and mechanisms of echolocation in whales. Utilized by the suborder Odontoceti or toothed whales (sperm whales, beaked whales, dolphins, porpoises, river dolphins, etc), echolocation is a sensory ability used to navigate and locate food underwater. By moving air through sinuses in their heads, whales create a variety of sounds and clicks by generating pressure waves from their melon. The sounds are broadcasted and reflected back from objects and researchers believe they are received by fat bodies which transmit sound from bones in the lower jaw through an oil-filled channel (Brill et al., 1988). Also called biosonar, whales neurologically process the information and use it to identify, locate and categorize environmental objects.
|© Timothy Morbey & Felix Marx|
- Beaked whale strandings in Greece in 1996 and again in the Bahamas in 2000 occurred at the same time that NATO and the U.S. Navy, respectively, were using high-powered sonar in nearby waters
- Fourteen beaked whales were stranded in the Canary Islands close to the site of international naval exercise in September of 2002.
- In 2003 five vacationing marine biologists came across two recently beached Cuvier’s beaked whales in the vicinity that a nearby ship (operated by Columbia University’s Lamont-Doherty Earth Observatory and funded by the National Science Foundation (NSF)) had been pulsing the ocean with high-powered sound waves to map the lithosphere beneath the ocean floor.
Sonar (originally an acronym for Sound Navigation And Ranging) is a technique that uses sound propagation to navigate, communicate with, or detect objects under the surface of the water. Active sonar is emitting pulses of sounds and listening for echoes – SOUND FAMILIAR? Donald Schregardus, a Deputy Assistant Secretary of the Navy explains that: “Sonar is the Navy’s eyes beneath the water”(A. Nevala, 2005). Along with mid-frequency sonar, airgun arrays used for geophysical exploration (important technologies with no alternatives) have been linked to whale strandings (Barlow et al., 2006). Mr. Schregardus does recognize that “one of our tools in use for 50 years may have detrimental effects on marine mammals under certain conditions” and the Office of Naval Research has launched a three-year $6 million research effort in fall 2007 ”(A. Nevala, 2005).
With a correlation between timing of strandings and heavy use of Sonar, environmental lawyers, scientists and the US military continue to argue about the actual effects that Sonar has on whales. Darlen Ketten, a biologist at the Woods Hole Oceanographic Institute, examined a set of stranded whales in the Bahamas in 2000 and reported the actual cause of death resulting from stranding (dehydration, stress, etc.), not blasts of Sonar (K. Madin, 2009). However, a brief paper published in Nature magazine presented evidence of acute and chronic tissue damage in stranded cetaceans that resulted from the formation in vivo of gas bubbles (P.D. Jepson et al., 2003). The whales stranded on the Canary Islands close to the site of a naval exercise in September 2002 were necropsied about 4 hours after the onset of mid-frequency Naval sonar activity. In theory the animals may have suffered from a marine mammal form of decompression sickness.
|© Pelagos Cetacean Research Institute|
When will we start valuing the welfare of non-humans on a level commensurate with what we value for ourselves? Maybe now is the time. Environmental organizations filed a lawsuit in December 2013 against the National Marine Fisheries Service to demand it to force the Navy to consider alternatives to its five-year plan that will intensify sonar use off Southern California and Hawaii. On top of conducting more research on the relationship of anthropogenic noise and Odontoceti strandings, we as a society have to decide which is more important: whale welfare or national defense? An easy question for some, but not for all.
Personally, I an just looking forward to all the future tours with my husband; who knows what controversy will be stirred up in next time!
NOTE: Non sibi ced patriae (not for self for country) is a Navy motto and cetus means whale.
Barlow, J., R. Gisiner. 2006. Mitigating, monitoring and assessing the effects of anthropogenic sound on beaked whales. Journal of Cetacean Research and Management. 7(3):239-249.
Brill, R.L., M.L. Sevenich, T.J. Sullivan, J.D. Sustman, and R.E. Witt. 1988. Behavioral evidence for hearing through the lower jaw by an echolocating dolphin (Tursiops truncates). Marine Mammal Science 4(3):223-230.
Jepson, P.D., M. Arbelo, R. Deaville, I.A.P. Patterson, P. Castro, J.R. Baker, E. Degollado, R.M. Ross, P. Herraez, A.M. Pocknell, F. Rodriguez, F.E. Howiell, A. Espinosa, R.J. Reid, J.R. Jaber, V. Marin, A.A. Cunningham, and A. Fernandez. 2003. Gass-bubble lesions in stranded animals: was sonar responsible for a spate of shale deaths after an Atlantic military exercise? Nature 425(6958):575-76.
Madin, K. 2009. Supreme Court weights in on whales and sonar. Oceanus 47:2.
Nevala, A. 2009. The sound of sonar and fury about whale strandings. Oceanus 47:2.
Peterson, G. 2003. Whales beach seismic research. Geotimes Jan2003:8-9 [Available at www.geotimes.org/jan03/NNwhaleshtml]