By Dawn M. Smith
Highland Wildlife Park in Scotland recently announced the birth of five wolf pups; the first European wolves born in Scotland since the species was extirpated, or locally extinct, in the late 1800s.
In an interview with Decoded Science, the park’s Animal Collection Manager, Douglas Richardson, talked about what was needed for the wolves to successfully raise this historic litter.
New Enclosure Encourages Wolves to Reproduce
Ironically the new enclosure is not larger than the old one; instead it is more wooded and complex, providing more privacy and environmental enrichment for the wolves.
Restricting visitor and vehicle access around the enclosure also allowed the wolves to escape from human noise and activity, both of which have been shown to decrease resting time in wolves in captivity, an indication of stress.
Adding further complexity to the wolf enclosure, there are three covered structures in the exhibit area and three more off-exhibit, for the wolves to use as den sites. Wolves in the wild commonly create multiple dens, and pups are moved from den to den. Having so many choices helps the wolves settle in, and the pair have now begun digging their own dens, a further indication that the adults are settling into their new home.
Chronic Stress and Wolf Populations
In the early 1990s, Carlstead and Shepherdson reported that chronic stress may compromise reproduction, and that environmental enrichment helps counter that stress. Anecdotal evidence from many captive wildlife facilities has since supported this research. The combination of a reduction in human impact and an increase in environmental complexity likely contributed to the success of the Highland Wildlife Park pack.
Hands–Off Management Leads to Five New Wolves at Highland Park
A more wolf-friendly enclosure is, however, just one aspect of ensuring successful rearing of wolf pups. Mr. Richardson noted that too much interference is often a problem when raising wolves in captivity. The temptation to check on the dens too often and too keep things too clean often causes stress for the female, which can lead to loss of pups. Once the adult wolves were observed to breed, human interference was minimized. The area was then closed to visitors and staff.
A small core of trained volunteers regularly monitored how often the female was visible. These volunteers dressed in street clothes rather than uniforms, as the wolves might interpret the presence of uniforms as an indicator that there would be people active in the enclosure. The female was visible more often than Mr. Russell would have liked, suggesting that she wasn’t taking good care of the pups, but the hands–off protocol was maintained.
As nail-biting as that time must have been, it was clearly the right decision, as evidenced on the day when the observers noticed a small dark lump moving on the female’s back. This was the first viewing of one of the new wolf pups.
The Highland Park Pack and Wolf Reintroduction
Given the historic aspect of the birth of this litter, Decoded Science asked Mr. Richardson about the potential for wolf reintroduction in Scotland. In addition to being extinct in the UK, populations of the gray wolf in Scandinavia, Poland, Germany, and the Western/Central Alps are listed as Endangered by the IUCN.Under the Bern Convention (Convention on the Conservation of European Wildlife and Natural Habitats)’s Action Plan for the Conservation of Wolves (Canis lupus) in Europe, Scotland is required to explore the possibility of reintroduction.
While acknowledging that there are many concerns to be addressed before any significant steps are made toward wolf reintroduction in the country, the park’s Animal Collection Manager expressed the hope that the birth of these pups would help trigger a new round of serious discussion on the subject. For now, however, Mr. Richardson is looking forward to the growth of the Highland Park pack, as these pups reach towards the age where they can help their parents rear the next litter.
Resources:
Sherratt-Ayerst, A. The effects of the enclosure and management on the behaviour of captive wolves (Canis lupus). UK Wolf Conservation Trust. Accessed July 12, 2012.
Carlstead, K., Shepherdson, D. Effects of Environmental Enrichment on Reproduction. (1994). Zoo Biology. 13:447-458. Accessed July 12, 2012.