Mexican Wolf - Adrienne Chin

MEXICAN WOLF  By: Adrienne Chin

Canis lupus baileyi   BIO 227 | Dr. Lisa Needles

Photo Sources (Left to Right, beginning in the top left corner:

          1. http://www.sciencemag.org/news/2017/09/endangered-us-wolf-denied-new-habitat-critics-charge-

politics-trumped-science

2. https://actionnetwork.org/petitions/protect-mexican-gray-wolves

3. http://www.azgfd.gov/w_c/wolf/naturalhistory.shtml

4. http://www.biologicaldiversity.org/species/mammals/Mexican_gray_wolf/

5. https://i.pinimg.com/736x/66/59/86/66598694d6c32649de26e8f84e579d81--mexican-wolf-the-mexican.jpg

6. https://cronkitenews.azpbs.org/2017/09/20/environmentalists-ranchers-trade-barbs-in-killing-of-mexican-gray-wolf/

7. http://news.stlpublicradio.org/post/scientists-breed-first-endangered-mexican-gray-wolf-frozen-semen#stream/0

DESCRIPTION & ECOLOGY

The Mexican wolf is the smallest, most endangered subspecies of the grey wolf. They live in mountainous forests, grasslands, and scrublands, and are native to the Southwestern United States and Mexico. The average Mexican wolf weighs between 60 and 90 pounds, is around 80 centimeters in height, and 135 centimeters in length.

Mexican wolves are known to be very social animals and live in packs consisting of an alpha male, alpha female, and offspring. Only the alpha male and female breed every year. Their most common breeding period is between the months of January and April depending on their location. Those living at lower latitudes breed more commonly in January and those living at higher latitudes breed more commonly in April. Mexican wolf litters usually consist of around six or seven pups and have a gestation period of around 63 days. These pups are born blind and taken care of by the pack until they gain their sight. They are fed regurgitated meat brought back from hunts.

Living in packs are helpful in giving each wolf a sense of security, while also making it easier to target prey. A system of hierarchy is used so that all the members of the pack work together to sustain each other’s lives. This species preys on animals such as deer, elk, and javelina. Their keen sense of smell is an excellent skill that assists in their ability to hone in on their prey.

 
Photo Sources (Left to Right):
1. http://www.timberwolfinformation.org/ca-san-diego-wildlife-advocates-pave-way-to-restore-gray-wolves-in-california/
2. https://www.azcentral.com/story/news/politics/arizona/2016/08/12/arizona-lawmakers-want-control-endangered-mexican-gray-wolves/88544828/

GEOGRAPHIC & POPULATION CHANGES

Mexican wolves were almost eliminated when humans implemented the use of traps and poison to kill the wolves. Many humans feared that the wolves would attack humans and their livestock, which was actually of rare occurrence. As the population of Mexican wolves quickly dwindled down, conservation specialists knew they had to take action to save the population of wolves before it was too later. Between 1977 and 1980, five wolves, four male and one female, were captured by Roy T. McBride from the US Fish and Wildlife Service. These five wolves were breeded under the care of conservation specialists with the intention of releasing them back into the wild, when an appropriate population size was reached. Their offspring eventually began to raise litters of their own, increasing the population of wolves under the care of specialists. After the reintroduction of Mexican wolves to the United States there was a significant growth in population. As of December 31, 2016, there are at least 113 Mexican wolves in the US, which is the largest population size to date.

Scientists have limited the geographic changes for the Mexican wolf population. When releasing wolves into the wild, they release them back into their natural habitat on either side of the Western Mexico-United States border. The main purpose for this is because Mexican wolves have low genetic diversity and have difficulties adapting to new habitats. Releasing them into an unfamiliar habitat may cause complications and decrease their population, making the breeding recovery plan essentially useless.

Photo Sources: 

1. https://www.fws.gov/southwest/es/mexicanwolf/pdf/2017MexicanWolfRecoveryPlanRevision1Final.pdf

DATE AND TYPE OF LISTING

The Mexican wolf has been listed under the Endangered Species Act of 1973 as an endangered species since April 28, 1976. It was moved to the Experimental Population, Non-Essential List on January 24, 1998.

CAUSE OF LISTING & MAIN THREATS

There are five main threats that the Mexican wolves face.

1. Destruction or threatened destruction, modification, or reducing of habitat
2. Overutilization for commercial, recreational, scientific, or educational purposes
3. Disease or predation from other animals
4. Current regulatory mechanisms are inadequate
5. Natural or manmade factors

One of the main threats to Mexican wolves are humans. Historically, Mexican wolves were often feared by humans, even though they it was rare to have a Mexican wolf attack a human or livestock. Mexican wolves were affected by traps and poisons put out to eliminate the species so they would not harm livestock. Even when the  killing of Mexican wolves was banned in some states, many illegal killings continued. Another large reason Mexican wolves are endangered is because they have extremely low genetic diversity. Therefore, they have a very difficult time adapting to new environmental conditions or exposure to new species of animals. This low genetic diversity is concerning for two reasons. The first being that, inbreeding reduces the size of the litter produced, which hinders the population growth. Another concern is that if disease or environmental catastrophe were to occur, it would most likely wipe out the majority of the Mexican wolf population.

Photo Sources: 

1. https://www.fws.gov/southwest/es/mexicanwolf/pdf/2017MexicanWolfRecoveryPlanRevision1Final.pdf

RECOVERY PLAN

There are six main recovery objectives for the Mexican wolf.

1. Increase the population of the two groups of Mexican wolves
2. Maintain the health of Mexican wolves and enhance their gene diversity
3. Create habitats that are able to support Mexican wolf populations
4. Improve the status of wild Mexican wolf populations through the Mexican Wolf Species Survival Plan (SSP) captive breeding program
5. Use education and outreach programs to raise awareness for Mexican wolf conservation
6. Ensure success of the recovery of the Mexican wolf population

1982 Mexican Wolf Recovery Plan

• There was no required numerical goal for the recovery
• The objective was to reach a population level that would sustain itself in the long-term
• Habitat reintroduction was used on both sides of the Mexico-United States border
• The plan was designed to strengthen regulations on Mexican wolf habitat protection and make society more involved in the recovery of the species
• The plan was revised many times improve its effectiveness

Captive Breeding Recovery Plan

• With breeding protocols kept in mind, between 1977 and 1980, five founder wolves were captured from the wild in Mexico
• This program breeds Mexican wolves until they are healthy and are in proper condition to be released into the wild
• Attempts to breed Mexican wolves to possess and retain a high level of gene diversity
• As of 2017, the gene diversity of the captive population is higher than that of the wild population in both the United States and Mexico
• Though gene diversity has increased, Mexican wolves are still very closely related and many scientists fear that one epidemic could lead to a fast declination of the population

Neither of these plans have been proved to be very effective and are currently being revised. A method to release more wolves that can maintain their health and population on their own is in the process of being made. Currently, there are around 97 Mexican wolves in the wild and many more will need to be introduced before it can be classified as safe from extinction.

For more detailed information on the Mexican Wolf Recovery Plans, please refer to the US Fish and Wildlife Service Full Mexican Wolf Recovery Plan.

https://www.fws.gov/southwest/es/mexicanwolf/pdf/2017MexicanWolfRecoveryPlanRevision1Final.pdf

WHAT CAN YOU DO?

One of the ways people can help Mexican wolves are to adopt! The Endangered Wolf Center offers the public to adopt a Mexican grey wolf pack or individual in their care. People have the option of adopting wolves by month or by year. More information on the adoption process can be found in the link below.

https://www.endangeredwolfcenter.org/adopt/mexican-wolves/

Defenders of the Wildlife also provides a list of ways that you can get involved in helping the recovery of the Mexican Wolf. If either becoming a Defender of Wildlife or receiving updates on the Mexican Wolf interest you, please visit the link below.

https://defenders.org/mexican-gray-wolf/what-you-can-do

OTHER RESOURCES

If you're interested in learning more about the recovery plan of the Mexican wolf, below is the full version.

https://www.fws.gov/southwest/es/mexicanwolf/pdf/2017MexicanWolfRecoveryPlanRevision1Final.pdf

Additionally, the Endangered Wolf Center, provides various facts on the ecology of a Mexican Wolf and what you can do to help them.

www.endangeredwolfcenter.org/educational-resources/mexican-wolf/

CITATIONS

• https://ecos.fws.gov/docs/recovery_plan/2017MexicanWolfRecoveryPlanRevision1Final.pdf

• “Mexican Wolf - Facts, Diet & Habitat Information.” Animal Corner, animalcorner.co.uk/animals/mexican-wolf/.
• Service, U.S. Fish and Wildlife. Species Profile for Mexican Wolf (Canis Lupus Ssp. Baileyi), ecos.fws.gov/ecp0/profile/speciesProfile?spcode=A00E.
• “Mexican Wolf.” Endangered Wolf Center, www.endangeredwolfcenter.org/educational-resources/mexican-wolf/.