loading page

Breeding pattern of Oreochromis niloticus (Linnaeus, 1758) (Pisces: Cichlidae) versus native congeneric species, Oreochromis macrochir (Boulinger, 1912) in the upper Kabompo River, northwest of Zambia
  • +1
  • Arthertone Jere,
  • Wilson Jere,
  • Austin Mtethiwa,
  • Daud Kassam
Arthertone Jere
Lilongwe University of Agriculture and Natural Resources Faculty of Natural Resources
Author Profile
Wilson Jere
Lilongwe University of Agriculture and Natural Resources Faculty of Natural Resources
Author Profile
Austin Mtethiwa
Lilongwe University of Agriculture and Natural Resources Faculty of Natural Resources
Author Profile
Daud Kassam
Lilongwe University of Agriculture and Natural Resources Faculty of Natural Resources
Author Profile

Abstract

Investigating the determinants of reproductive biology of fishes is an essential component of biological research. Breeding pattern was investigated to determine the impact of exotic Oreochromis niloticus on the native congeneric Oreochromis macrochir in the upper Kabompo River. Gonado-somatic index and sex ratio was used to investigate the breeding pattern in both invaded (where O. niloticus is present) and uninvaded (where O. niloticus is absent) sections of the river. Oreochromis macrochir was the only native congeneric species found in both sections. Results showed that the overall gonado-somatic index means for both sexes of O. macrochir in both sections were similar. For O. niloticus in invaded section indicated all year reproduction though reduced spawning in cold season (May-June), but with increased spawning activity in wet season (February-March). In O. macrochir, males and females were found breeding in both dry and wet seasons only, as for cold season no reproduction was recorded. Sex ratio (females: males) was 1:1.3 and 1:1.7 for O. niloticus and O. macrochir respectively, and both significantly deviated from the sex ratio of 1:1 (ꭓ2=8.42 and 9.37; p<0.05). Oreochromis niloticus formed the most abundant fish caught 221(63.5%) than O. macrochir 127(36.5%). Our study has revealed that O. niloticus was able to spawn in all seasons with 23% higher breeding population than O. macrochir, which explains the suppression in the abundance. We expect O. niloticus to invade further downstream of the Kabompo River due to natural dispersion.

Peer review status:ACCEPTED

01 Sep 2021Submitted to Ecology and Evolution
02 Sep 2021Submission Checks Completed
02 Sep 2021Assigned to Editor
06 Sep 2021Reviewer(s) Assigned
26 Sep 2021Review(s) Completed, Editorial Evaluation Pending
28 Sep 2021Editorial Decision: Revise Minor
13 Oct 20211st Revision Received
13 Oct 2021Assigned to Editor
13 Oct 2021Submission Checks Completed
13 Oct 2021Review(s) Completed, Editorial Evaluation Pending
18 Oct 2021Editorial Decision: Revise Minor
27 Oct 20212nd Revision Received
28 Oct 2021Submission Checks Completed
28 Oct 2021Assigned to Editor
28 Oct 2021Review(s) Completed, Editorial Evaluation Pending
29 Oct 2021Editorial Decision: Revise Minor
30 Oct 20213rd Revision Received
01 Nov 2021Assigned to Editor
01 Nov 2021Submission Checks Completed
01 Nov 2021Review(s) Completed, Editorial Evaluation Pending
05 Nov 2021Editorial Decision: Accept