Candace Calloway Whiting
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Swimmer Interdiction Security Dolphins: Are They Here?
Dolphins in the military (Creative Commons Photo)
Orca Network reports that a bottlenose dolphin, (which normally prefer warmer water and rarely venture into the cold water of Puget Sound) has been seen several times in the vicinity of the Port of Tacoma. According to Cascadia Research, there have only been two documented occurrences of bottlenose dolphins here previous to this one, in 1988 and one recently, in June of this year, both of which were identified following their death.
The most logical explanation for these unusual appearances is that the dolphins somehow became disoriented and strayed from their normal environment, and as unfortunate as that may be it is not that unusual for dolphins and whales to become ill or injured and lose their bearings. The characteristics of the ocean this year brought warmer water offshore, so it is possible that a small pod of dolphins followed fish northward. Given that a deceased bottlenose dolphin was also found in June, it could well be that several came north together and the one we are seeing now is the lone survivor. Often in nature these experiments - where animals wander outside of their normal range - are indicative of changing climatic conditions, or general loss of resources in their usual habitat. Although sometimes these emigrations are successful, leading to the establishment of new populations, often the animals find themselves in very marginal conditions and don't thrive.
That said, it is also possible that the more recent sightings are linked to the navy's planned marine mammal underwater surveillance, the Swimmer Interdiction Security System (SISS) at the Naval Base Kitsap-Bangor. After a three year process of obtaining permits and doing an environmental impact study, the navy announced in early 2010 that the program to use dolphins and sea lions to patrol the waters of Puget Sound would be implemented within the calendar year:
The dolphins and sea lions are the stars of a new swimmer interdiction security system, but like nuclear warheads, the Navy will neither confirm nor deny their presence.
"Because it's a security system, we are not going to discuss when or if the animals are there," said Tom LaPuzza, spokesman for the Navy Marine Mammal Program in San Diego. He added, however, that, "You can go by there in your boat and see them and know they are there."
They're evidently not there now because their homes haven't been built, LaPuzza said. Construction can't begin until the fish window closes in July.
LaPuzza doesn't know yet how many animals will be heading north. There will be a total of no more than 20, according to the Final Environmental Impact Statement prepared for the program.
Four floating enclosures, 30 feet long by 30 feet wide, will each house up to four dolphins. Their water temperature will be kept at a minimum of 52 degrees.
(Komo News, May 2010)
In the photo of the dolphin that is now in Puget Sound, you can see that although it's skin looks bumpy the animal appears to be in good weight. You might assume that the navy would not work a dolphin that was sick, but it is not possible to tell from the photo if the dolphin has a skin ailment, or whether it is the normal response these warmer water species have to cold water.
This bottlenose dolphin was photographed in southern Puget Sound in mid-December. (Photo by Josh Oliver, courtesy Cascadia Research)
"Skin lesions are indicators of cold stress in marine animals because they can occur as a direct result of prolonged exposure to cold, although other indicators (such as increased respiration rate) are likely to be observed before onset of skin discoloration occurs. Thus, skin discoloration would be considered as a secondary indicator of cold water stress, and more than one secondary indicator would be needed to ensure that skin discoloration is representative of cold water stress for any specific individual."
In terms of working an animal that shows signs of cold intolerance, the navy has a set protocol that determines when the dolphins must be pulled from the cold environment, and since the skin bumps are considered a secondary reaction, the animals are allowed to work with this condition:
"Although trainers and handlers monitor marine mammals constantly during open-water work, special care would be taken for cold-stress indicators when animals are working in water temperatures approaching the LCT of the animal. The animals would be continuously monitored for increased respiration rate, behavior change, and shivering. Other secondary indicators (skin discoloration, weight loss) would not be evident during individual sessions because these conditions occur over a longer period of time, and thus would be considered as part of the longer term monitoring program. When during a session the thresholds for the secondary indicators of increased respiration rate, shivering, and behavior changes are exceeded, the core body temperature of the animal would be measured. Measurements would be repeated at 30-minute increments until the end of the session. The method of core body temperature measurement would be one of several approved for use in MMP animals by the veterinary staff (e.g., rectal temperature probe, stomach temperature pill, implantable temperature sensor, etc.)."
So it is possible that this is one of the dolphin sentries, either in training or possibly having temporarily strayed from the handler's control.
Although the navy says that the actual work will be carried out at night, significant training needs to be accomplished before the animals will reliably perform their duties and return to the boat when recalled, and this is more easily done during the day. The animals need to get used to their enclosures, and possibly new trainers and handlers. They need to become familiar with the basic environment in the areas of Puget Sound where they will be expected to work, and will need to adjust to the lower water temperature (it can be a full 10 degrees colder here than the water in San Diego, where their initial training takes place).
Under the best of circumstances, dolphins can refuse to work and ignore the handler's commands to return to the boat - and if the animals don't know where 'home' is, they might wander around for hours or days before being located:
"Trained marine mammals may also fail to obey simple commands from their trainers when exposed to colder temperatures, particularly with respect to behaviors that require exposing skin to air temperatures below freezing (Scronce and Bowers 1985). Deviations from normal behavior, such as altered swimming behavior and refusal to beach, might be good indicators of cold stress because they can indicate that the animal is trying to minimize exposure to cold temperatures."
"When an MMP marine mammal becomes separated from its workboat, trainers recall the animal with an acoustic recall pinger. The pinger is a low-power, sound generator that is lowered by hand into the water from the side of a boat. The pinger is omni-directional, and the sound is transmitted into the water. This pinger is a commercial device that has been used for many years by the MMP. The marine mammals are trained to respond to
the sound from the pinger as an emergency recall.
Each animal is also outfitted with radio and satellite transmitters that can be used to locate an animal when it is out of range of the acoustic pinger recall. Program personnel are well trained in the use of these tracking devices and can quickly ascertain a marine mammal's location. When the MMP marine mammal is located, the trainers travel to the animal and then use pingers and positive reinforcement behaviors to retrieve the marine mammal... If neither a pinger nor a transmitter can locate the marine mammal, the first location physically searched is the MMP home enclosure. This is the most likely location where animals are found. If the animal is not found at the MMP enclosures, satellite telemetry system tracking for the animal commences."
Whether this dolphin is wild or trained, lost or working, it does serve as a reminder that these animals will soon be swimming in the Puget Sound, patrolling to help keep intruders from attacking our shores. Whether we like it or not, the navy considers these sentries to be vital to our safety. They strive to take good care of the dolphins, if for no other reason than that these animals represent a huge financial investment and significant commitment of resources.
The quoted information on the SISS program was obtained from a navy document, the appendix of which alone is 110 pages:
APPENDIX A
NAVY MARINE MAMMAL PROGRAM
SSC SAN DIEGO
SPACE AND NAVAL WARFARE SYSTEMS CENTER
53560 HULL STREET
SAN DIEGO, CALIFORNIA 92152
If you are curious about the ocean temperatures, this is a good source:
Water temperature
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