Save the Sperm Whales

Save the Sperm Whale 

by Zach Baker

Description and Ecology of Organism

The Sperm whale or “Physeter macrocephalus”  falls under the category of  The  size of the sperm whale is larger than the the average school bus.  They are the only marine mammals with a blowhole that is a-symetrically placed on their heads  and are generally grey in color with white markings around their mouths. Sperm whales have extremely large heads taking up almost half of their body size; and at their largest can grow up to about 60 feet. The sperm whale travels in small pods of around 20 whales, and usually maintain regular family groups. The sperm whale’s diet consists mainly of large squid but will also consume sharks, and other fish. The sperm whale obviously has an interesting name — the name comes from the large amount of fluid held in their heads called spermaceti, and when cooled down turns into a waxy substances that can be used in oil lamps, candles and so on and so forth. This liquid was extremely important in the old days, and Sperm Whales were commercially harvested for it; the whalers at the time mistaked this white fluid as the sperm of the wale, and hence forth came the name

Geographic and Population Changes

The populations of sperm whales are un-known; but since there was un-restricted whaling for about two decades and considering the extremely large amount of whales that were killed during this time period they were most like likely placed on the endangered list even with out an accurate reading. Sperm whales are almost impossible to get an accurate read on population as they generally inhabit waters below 600 feet deep, are able to submerge to around 3k feet deep, and in-habit such a vast area of the globe. The best estimate of the population of Sperm Whales is in between 200k and 1500k.  As you can see the distribution of sperm whales is extremely large and essentially covers the majority of the globe; These whales will travel from about 60 degrees north to about 70 degrees south. Generally, the male sperm whales will travel in groups far more north than the females seeking  out prey; the females generally stay with their calves  in tropical or sub tropical waters.  

Listing Date and Type of Listing

The sperm whale is currently listed globally as endangered on the ESA, and depleted on the MMPA. Because of the inability to get an accurate read on It is assumed that they were  placed on the endangered act due to the extreme amounts of un-regulated whaling that took place before the IWC in 1946 (international whaling commission) initiated regulations to conserve the species. It is estimated that in between 1800 and 1909, close to 700k whales were harvested. It is assumed that the population had decreased exponentially due to the unrestricted whaling in the past. 

Cause of listing and Main threats to continued existence

The main threats to the existence of Sperm Whales include: 

Fishery Interactions:  Sperm whales sometimes are caught in deep sea neats laid out by fishermen; in the case that they break through these nets, they sometimes will either become deformed by the constraints it places on them; or will drown trying to remove these nets. there is also risk of fisherman harming whales as they try and take their catch as prey. 

Anthropogenic Noise: As these marine mammals use sound to communicate, the sound that humans have introduced like large vessels, oil rigs, and even the invention of sonar into the oceans could be harmful to their abilities to communicate and navigate around the seas. No research done on this has been conclusive so there is no conclusive proof that ocean noise affects these creatures. 

Ship Strikes: When sperm whales come up for air after long dives; they are very susceptible to being hit by passing ships. There are numerous accounts of sperm whales becoming very injured and dying after either colliding with a ship; or getting cut by it’s propellors. 

Contaminants and Pollutants:  Contaminants and pollutants that have been found in whale caucuses have been alarmingly high and potentially toxic, including mercury and several toxic metals. Another risk is the large amounts of pesticides leaked into the water such as DDT. Oil Spills are also a large concern for the current Sperm Whale Populations as the oil contaminates food sources and can cause health risks in whales such as Pneumonia.  

Disease: As many of the pollutants found in whales are known to suppress the immune system these mammals become more susceptible to disease . 

Injury:  from Marine Debris: Essentially Human trash; consisting of synthetic plastics that are not biodegradable like plastic bags, bottles, ropes, nets, balloons, rubber etc. When ingested these cause physical blockage in the digestive system, which can lead to death. 

 Predation/Natural Deaths:  This is just the Circle of Life, and the predation of whales by other larger predators. Sperm Whale Calves are consumed by killer whales, and large sharks. 

Whaling:  Even with the IWC’s regulation on commercial whaling has decreased this threat, whaling sad continues and is a direct threat to this species survival. There is currently a ban on whaling; except for in Norway and Iceland (who have objected to the IWC (international whaling commission) and Japan who takes whales for “research”.

Description of Recovery Plan

This information is based off off the “Final Recovery Plan for Sperm Whales” published by the National Marine Fisheries Service, and the National Oceanic and Atmospheric Administration in 2010 and consists of 8 steps. 

1. Coordinate to implement recover actions and maintain the current regulation on sperm whales. 

this would essentially create widespread cooperation of international  governments to maintain the regulations of whaling in their specific waters. As whales are so widely dispersed this is absolutely necessary in the conservation of their species. 

2. Figure out better ways to assess the population of the sperm whale. 

Even though large amounts of energy have been expended trying to figure out the population of sperm whales; it has not been able to give an accurate read. New methods of population monitoring need to be developed in order to achieve  this; in collaboration with many scientists in foreign waters. 

3. determine population discreteness and population structure of sperm whales. 

As there is not a lot of insight on the lives of sperm whales more research must be done on the species. in order to gather this information the recovery plan calls for genetic analysis of whale, the use of telemetry and photographic documentation to track their movements, and find out more information about the social structure of these mammals. 

4.  Conduct risk analysis in each ocean (Indian, Atlantic,Pacific) 

to gain an accurate read into population projection and to eventually to find an estimated risk of extinction 

5.  Identify, Characterize, Protect, and Monitor Habitat Important to Sperm Whale Populations in U.S. Waters and Elsewhere. 

In order to maintain a sperm whale population, the habitats in which they mainly maintain must be preserved as well. 

6. Investigate Causes and Reduce the Frequency and Severity of Human-caused Injury and Mortality. 

7. Monitor Habitat Important to Sperm Whale Populations in U.S. Waters and Elsewhere

8. Maximize Efforts to Acquire Scientific Information from Dead, Stranded, and Entangled Sperm Whales. 

Personal Action? 

To help save these endangered species from commercial harvest and whaoise pollution; we can donate both our time and our money to organizations whose mission is to save the whales. Another simple way is to try harder to keep our oceans clean; by picking up trash at the beach and trying harder not to pollute the water supply by using harsh chemicals and herbicides. see http://www.pacificwhale.org/content/action-center for more information. 

sources: 

http://animals.nationalgeographic.com/animals/mammals/sperm-whale/

http://www.fisheries.noaa.gov/pr/species/mammals/whales/sperm-whale.html

http://www.pacificwhale.org/content/action-centerhttp://www.pacificwhale.org/content/action-center