Stressors and African Wild Dogs

Photo from https://www.worldwildlife.org/species/african-wild-dog

This may be one of the coolest looking animals out there in my opinion. The endangered African wild dogs are fighting a losing battle against many different stressors. As with many species around the world habitat loss is affecting African Wild dogs as well. This species used to be found throughout much of Africa and today are confined to a few areas.  There are roughly only about 5,000 African wild dogs remaining in the wild today due to habitat loss and other human and non human stressors (Creel et al. 1997).

This figure shows the range of the African wild dogs today. Figure from https://ohiostate.pressbooks.pub/sciencebites/chapter/africas-vanishing-predator-the-african-wild-dog/

Habitat loss has caused the population as a whole to become separated from each other and be isolated from reproducing with each other. This is causing stress in the animals as it is harder to find packs which is a major component of their live’s. This is because African wild dogs are relatively small and need packs to hunt down prey and they have to compete for for with larger carnivores such as lions and the other canine of Africa the Hyena. This competition with other carnivores has accounted for about 15% of wild dog deaths in an area of research (Creel 1997). If the other carnivores don’t necessarily kill the wild dogs directly they could indirectly be affecting the animals by stealing their food. On average, Gormon et al. 1998, found that wild dogs spend 3.5 hours a day hunting and if they lose 25% of their meals to other carnivores then they have to hunt for 12 hours which dramatically increases their energy budget. Since they are so small it takes lots of energy to successfully take down Antelope and other food sources thus, the need for large pack numbers. It was found that the cost of hunting for African wild dogs was estimated to be twenty five time that of their basal metabolic rate which adds to the importance of them losing food that do do manage to successfully acquire to large predators(Gorman et al. 1998). If there are smaller pack sizes, as there is in today’s world, then more energy is having to be devoted to hunting rather than reproduction which would help increase the population sizes. In addition for hunting success studies by Lindsey et al. 2003 found that in order for packs to have reproductive success packs with at least five individuals are needed. However, the hunting/pack size of African wild dogs isn’t the leading factor in the cause of death in Selous Africa where a study was conducted. About 69% of wild dog deaths were related to the stressor of competition with the species (Creel 1997). This is due to the killing of pups when another male comes into the pack and fighting within the pack for food. Due to the low population numbers Creel et al. 1997 place radio collars on individuals and tested whether or not their stress levels were different and found no stress level differences between non-collared individuals versus collared individuals by measuring corticosterone levels from the animals. This was because they were worried that increased stress levels would suppress the immune system resulting in decreased fitness of individuals. This studied showed that the collaring of African wild dogs could be used to help monitor the population without worrying about the fitness of the animal decreasing. This is sadly not the only way that humans are impacting these animals. Wild dogs will frequently attack and kill domestic farm animals because they are an easy food source. This however leads to farmers targeting these animals and killing them just like how farmers in the U.S. kill wolves that attack their cattle. On top of this the wild dogs frequently pick up diseases from the domestic animals that they kill. African wild dogs are facing all kinds of stressors in the world today which are contributing to the declining population and if we do not help at least conserve habitat then the painted dogs may soon become extinct.

References:

Creel S., Creel, N., Monfort, S., 1997, Radiocollaring and and Stress Hormones in African Wild Dogs. Conserv. Bio. 11: 544-548.

Creel, S., Creel, N., 1997, Six Ecological Factors that may Limit African Wild Dog. Anim. Conserv. 1: 1-9.

Gorman, M., Mills, M., Raath, J., Speakman, J., 1998, High hunting costs make African wild dogs vulnerable to kleptoparasitism by hyenas. Natur. 391: 479-481.

Lindsey, P.A., du Toit J.T., Mills, M., 2003, Area and prey requirements of African wild dogs under varying habitat conditions: implications for reintroductions. South African Journ. of Wild. Resear. 34(1): 77-86.

 

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