How do you tell if a mud crab is reproductively mature? And why do you need to know this?
WCS intern, Mildred Kelokelo, based in Kavieng, has just completed a month’s training acquiring skills in methods for the rapid reproductive analysis of reef fishes and invertebrates with her work focusing on mud crabs.
Mildred was part of the 2015 Bishop Museum’s Pacific Biological Survey (PBS) program that was conducted from 9th March to 3rd April at Nago Island Mariculture and Research Facility in Kavieng, New Ireland Province.
The PBS program was a training opportunity for fishery researchers and managers to undertake and learn methods in “jungle histology”: a rapid, low-cost, on-site, histology-based reproductive analysis that require minimal equipment.
This program involved four participants. Mildred was the only female among the three fisheries specialists from US-associated Pacific Island region nations.
For a recent graduate in the field of Fisheries and Marine Resources, Mildred felt privileged to have attended the training with some of the Pacific’s fisheries experts. She added that working with them has given her the opportunity to learn from their knowledge and field work.
“It was a great experience for me”, she said, “I have gained research skills and knowledge in crab and reef fish reproductive methods and how to analyse and interpret data.”
The participants were involved in examining the length-weight relationships, size-at-maturity, reproductive mode, size-specific sex ratios, size-fecundity relationships and reproductive periodicity of five different species.
Bishop Museum’s recent innovations have enabled reproductive information to be generated quickly, with minimal gear and cost. This has the potential to eliminate previous impediments to broad-scale reproductive analysis of Pacific coral-reef fishes.
Mildred’s work focused on the reproduction of the mud crab Scylla serrata
, a species of great importance as a food resource and income source for communities and part of WCS’s programme to ensure sustainable small-scale fisheries in New Ireland Province.
“We need to know the size of maturity in mud crabs to ensure that communities do not collect immature animals before they have an opportunity to breed. Mature crabs must produce many eggs and young to ensure the sustainability of further crab harvesting,” she explained.
The outcome of her work during the course will help the WCS programme provide recommendations to local communities who are interested in the conservation and long-term harvest sustainability of mud crabs. Other management recommendations include not collecting ‘berried’ (crabs with developing eggs) female crabs.
Mildred’s attachment as an intern with the WCS New Ireland program is supported under the David and Lucile Packard Foundation funded project and this in-depth course provided further training and skills to her internship.