Killer Whale Recovery Plan

Carter Chillingworth

Description:

(Size of human Compared to Killer Whale)

The killer whale, also referred to as the orca which means "the shape of a barrel or cask", belongs to the oceanic dolphin family (Wikipedia, Killer Whale). Due to their vicious reputation killer whales are also referred to by the Spanish as Ballena Asesina, meaning "assassin whale" (Marinebio, Orcas). Male killer whales can grow to be about 23-30 ft in length, and females can grow to be about 20-26 feet in length which makes them the largest species that is part of the dolphin family (Marinebio, Orcas). Killer whales are more generalists than they are specialists when it comes to their habitat and their prey. They can be found all over the
world, from frigid antarctic waters to warm tropic waters although they prefer higher latitudes and coastal areas. Unlike most whales, killer whales have teeth that are covered with thick enamel, which allows them to eat a variety of fish and other sea life such as fish, seals, squids, sea turtles, penguins, polar bears, and even other killer whales (Marinebio, Orcas). Killer whales, much like wolves, work together to hunt for food in groups known as pods, and each pod tends to consume more of one prey species than others depending on their location. Killer whales typically live to be around 29 years old on average, but have the potential to live 50-60 years (Wikipedia, Killer Whale). Although similar, there are three genetically distinct classifications of killer whales: resident, transient, and offshore. Although the habitats of these whales overlap, their genetic variance keeps them from interbreeding.

(Marinebio, Orcas)

Geographic and Population Changes:                                    

(Population Spread)
(Marinebio, Orcas)

Besides humans, orcas are the most widely distributed mammal, which explains why they were described as early as 1558 by Konrad Gessner (Wikipedia, Killer Whale). However, studies indicate that the largest densities of killer whales reside in the northeast the Atlantic, north Pacific, the gulf of Alaska, and off the coast of Antartica (Wikipedia, Killer Whale). The current population estimate for killer whales is a minimum of 50,000 individuals, and have had a population decline of 20% from 1996-2001 (NOAA Fisheries, Killer Whale).                                        

Listing Date and Type of Listing:

The killer whale was designated as endangered under the Endangered Species Act (ESA) on November 18, 2005, and are still defined as endangered today. Before being listed under the ESA, killer whales were labeled as below optimum sustainable population by the National Marine Fisheries Service (NMFS), and was flagged as being depleted under the Marine Mammal Protection Act (MMPA). 

Cause of Listing and Main Threats to its Continued Existence:

(Killer Whale Recovery Plan)

Just like many other marine animals habitat destruction and degradation, overfishing, changes in food availability, pollution, climate change, and human disturbance are all factors believed to affect killer whales (Killer Whale Recovery Plan). While it is certain that all of these factors contribute to the population decrease of killer whales, there is not an identifiable main threat to their existence due to their elusiveness and spread throughout our worlds' waters. Although the cause is not solely recognizable killer whales fall under the appropriate requirements to be considered threatened or endangered, "(1) the present or threatened destruction, modification, or curtailment of its habitat or range; (2) overutilization for commercial, recreational, scientific, or educational purposes; (3) disease or predation; (4) inadequacy of existing regulatory mechanisms; or (5) other natural or human-made factors affecting its continued existence" (Killer Whale Recovery Plan).

Description of Recovery Plan:

Due to a lack of knowledge on what exactly is causing the killer whale decline it has been difficult to determine the precise needs for conservation and recovery for the population. Because there is no single identifiable cause, the recovery plan addresses multiple problems that will be altered accordingly based on further research by the NOAA and other organizations. The recovery plan identifies four major concerns:

1.) Reduction in quantity or quality of prey

2.) High levels of organochlorine pollution and emerging levels of other contaminants (which can cause immune and reproductive problems)

3.) Sound and disruption from boats

4.) Oil Spills

(Killer Whale Recovery Plan)

While the recovery plan focuses on the above issues, education, outreach, and response to stranded killer whales are also goals. 

FUN FACT: While Killer whales may have an intimidating name, there has never been a report of an attack on a human being.

http://en.wikipedia.org/wiki/Killer_whale#Taxonomy_and_evolution 

http://marinebio.org/species.asp?id=84

http://www.killer-whale.org/killer-whales-endangered/

http://www.nmfs.noaa.gov/pr/species/mammals/whales/killer-whale.html

http://ecos.fws.gov/docs/recovery_plan/whale_killer.pdf