Dynamic Modelling for Tristan Albatross Conservation
| The Tristan Albatross, a seabird that breeds primarily on Gough Island in the Atlantic Ocean, is currently Critically Endangered. The System Dynamics methodology created by Jay Forrester, coupled with the processing of spatial data sets in Python and R, was used to investigate the characteristics of an effective intervention to protect this species. Using the current best estimates of adult survival rate and breeding success (the percentage of eggs that survive to become juvenile albatross), the Tristan Albatross is expected to exhibit a decline of 6.7± 0.2%; when fisheries by- catch is addressed without changing mouse predation this decline can be reduced to 2.0 ±0.1%, and when mice impacts are addressed without modifying fisheries bycatch this decline is projected to reduce to 4.6 ±0.1 %. Given the population dynamics of the Tristan Albatross, a minimum adult breeding rate of approximately 95.3% is estimated to be necessary in order for the population to be stable, provided that the breeding success rate is equal to the natural breeding success rate. It was concluded that the most practical intervention to cease the population decline of the Tristan Albatross would likely entail both the eradication of mice from Gough Island and a reduction in fisheries bycatch of approximately 94%. The spatial areas with highest potential for bycatch mortality have been identified. Finally, it was found that eradicating mice from Gough Island would also eradicate a credible risk that climate change could impact the Tristan Albatross population by increasing the densities of the mice population. |
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