A level Biology 18.3 Conservation- Exam style question – Paper 4

Question

 The IUCN Red List provides information about the conservation status of species throughout the world, including the American badger, Taxidea taxus, and the black-footed ferret, Mustela nigripes.

Fig. 2.1 shows an American badger and Fig. 2.2 shows a black-footed ferret.

Fig. 2.3 shows the IUCN conservation status of the American badger and the black-footed ferret in 1987 and in 2013.

(a) American badgers and black-footed ferrets are both predators.

• American badgers feed on prairie dogs and a range of other animals.
• Black-footed ferrets feed almost entirely on prairie dogs.
• American badgers do not have any animal predators.
• Black-footed ferrets are preyed upon by American badgers and several other predators.

Suggest reasons why black-footed ferrets are an endangered species but American badgers are not.[2]

(b) In 1987, the world population of black-footed ferrets consisted of only 18 animals living in captivity. A number of different agencies worked together to prevent the extinction of this species. Their goal was to produce young black-footed ferrets to be released into the wild. The survival and breeding of the animals in the wild would then be monitored and supported.

The collaborating agencies included:

• local government
• universities
• zoos
• native tribes that owned undeveloped reservation land.

Outline how these different agencies could contribute to successful conservation of the black-footed ferret.[3]

(c) Black-footed ferrets were released at three different locations in the wild at different times. Each population was established from captive-bred animals.

Fig. 2.4 shows the population sizes of black-footed ferrets at the three release locations.

(i) Describe the patterns of population growth at the three locations where black-footed ferrets were released.[3]

Table 2.1 shows information about the gene pool of the populations of black-footed ferrets and the leg sizes of the black-footed ferrets at each release location in 2004.

All three populations were started by animals from the same captive population. In this original captive population, 100% of the genes surveyed showed polymorphism, that is, they had more than one allele. The mean number of alleles per gene locus was two.

The population at the South Dakota location in 2004 maintained the same level of genetic variation and leg size data as the original captive population, but the populations in Wyoming and Arizona showed changes.

(ii) Use Table 2.1 to describe how the gene pools and leg sizes of the Wyoming and Arizona black-footed ferret populations have changed, compared to the original captive population.[2] 

(iii) With reference to Fig. 2.4, suggest reasons for the changes you have described in (ii).[3]

(d) In 2008 some black-footed ferrets were born in captivity as a result of IVF using frozen sperm that had been stored for several years.

Explain the benefits of using frozen sperm in captive breeding programmes.[3] [Total: 16]