Study

The role of commercial crocodile farming in crocodile conservation

  • Published source details Blake D.K. & Loveridge J.P. (1975) The role of commercial crocodile farming in crocodile conservation. Biological Conservation, 8, 261-272.

Actions

This study is summarised as evidence for the following.

Action Category

Head-start wild-caught reptiles for release: Crocodilians

Action Link
Reptile Conservation

Relocate nests/eggs for artificial incubation: Crocodilians

Action Link
Reptile Conservation
  1. Head-start wild-caught reptiles for release: Crocodilians

    A replicated study in 1967–1974 in three sites along the Zambezi River in Zimbabwe (Blake & Loveridge 1975) found that some released head-started Nile crocodiles Crocodylus niloticus survived at least six months in the wild, and that mortality during head-starting was highest during the first year. Over seven years, hatching success of Nile crocodile eggs in a head-start programme was 74% (16,697 of 22, 697 eggs hatched). In one site, hatchling mortality from six annual cohorts was 8–52% in the first year, 1–14% in the second year and 0–4% in the third year (see original paper for further details). Twenty of 53 (38%) released head-started crocodiles were caught at least once in four years following release (see original paper for details). In 1967–1973, Nile crocodile eggs were collected from the wild, and hatchlings were head-started at three rearing stations (at Kariba, Binga and Victoria Falls) as part of a crocodile farming initiative (128–2,475 eggs collected/station/year). Eggs were artificially incubated in captivity (no details are provided). An annual quota set by the government required 5% of three-year-old crocodiles were returned to the wild. In total, 355 head-started crocodiles were returned to the wild by the end of 1973, of which 53 released into one site were monitored by twice-yearly recapture surveys in 1970–1974.

    (Summarised by: Katie Sainsbury)

  2. Relocate nests/eggs for artificial incubation: Crocodilians

    A replicated study in 1967–1974 in three rearing stations along the Zambezi River in Zimbabwe (Blake & Loveridge 1975) found that three-quarters of artificially incubated Nile crocodile Crocodylus niloticus eggs hatched in captivity. Over seven years, artificially incubated Nile crocodile egg hatching success was 74% (16,697 of 22,697 eggs hatched). The authors reported that collecting eggs very soon after laying had a detrimental effect on hatching success. Nile crocodile eggs were collected from the wild, hatched and reared in three rearing stations (at Kariba Lake, Binga and Victoria Falls) as part of a crocodile farming initiative in 1967–1973 (128–2,475 eggs collected/station/year). Eggs were artificially incubated in captivity (no details are provided).

    (Summarised by: Katie Sainsbury)

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