Traditional Ecological Knowledge and scientific inference of prey availability: Harvests of sooty shearwater (Puffinus griseus) chicks by Rakiura Maori

Abstract

This study of customary harvests of sooty shearwater Puffinus griseus chicks by Rakiura Maori compares the utility of Traditional Ecological Knowledge (TEK) and ecological science for understanding patterns in prey availability. We recorded TEK of 28 muttonbirders about emergence patterns and variation in chick size at different aspects of 14 breeding islands and in their coastal fringe compared to inland areas. Spatial and temporal variation of chick availability were measured using the methods of ecological science in the 2001 harvest season across Putauhinu Island, south west of Rakiura, New Zealand. As predicted by TEK, titi emerged earlier from west than east coast locations on Putauhinu. Z08034; Online publication date 31 August 2009 Received 5 November 2008; accepted 1 June 2009Scientific measures were also consistent with an earlier emergence in coastal compared to inland areas as asserted by TEK, but conclusive inference is potentially confounded by movement of chicks between burrows just before fledging. A TEK construct predicting heavier chicks on the west coast was not supported by scientific measurements. We also measured the characteristics of areas preferred for harvesting so that we could gauge representativeness of the areas "sampled" by the muttonbirders to accumulate their TEK. Within forested habitat, areas harvested by muttonbirders had 62-65% higher chick density than unharvested areas. The muttonbirders concentrated harvesting where there was less ground cover and taller canopy cover and only hunted on nights and times of the season when harvesting was most profitable. Therefore, TEK may be less able to detect wider-scale variation and harvest impacts on prey in particular. Short runs of scientific information from spatially and temporally stratified sampling will complement and assist inference from longer term TEK. As shown in this case study, TEK and science often agree on pattern, but are likely to disagree on why a pattern exists.

Collaborative Engagement of Local and Traditional Knowledge and Science in Marine Environments: A Review

“…Daw et al (2011) compares fishers' reports of catch rates with official landings data and underwater visual census (UVC) in the Seychelles, finding that each data source gave different perceptions of trends in the biomass of fish and catches over the study period. Other such studies have compared seasonal abundance patterns (Manajarréz-Martínez et al 2010) and seabird chick emergence and size (Moller at al. 2009a).…”

Denning behaviour of ship rats (Rattus rattus) on Taukihepa, a seabird breeding island

“…36 The aim of this study was to determine which microhabitat characteristics were common to ship rats' den site areas on a seabird island, and to investigate the social organisation within these dens. This study supported research on the impact of rats on tītī/sooty shearwater (muttonbird) {Puffinus griseus) being carried out by Kia Mau Te TUT Mo Ake Tōnu Atu ("Keep the Tītī Forever") research group, in collaboration with Rakiura Māori, into the impact of predators, climate change and large scale cultural harvest on the sustainability of tītī populations on tītī islands (Moller et al 2003(Moller et al , 2009afletcher et al in press).…”

“…Tītī breeding burrow density is lower where leaf litter and ground debris is thicker (Moller et al 2009a;charleton et al in press), yet dens were not apparently associated with more or less litter, ground cover or higher density of shearwater burrows. This suggests that den site selection has little to do with proximity to food on Taukihepa.…”

Looking after your ground: resource management practice by Rakiura Maori Titi harvesters

“…In some open systems, families allocate different times of night to harvest during rama, so that they do not deplete the number of emerged chicks available for capture. Some birders harvest during the early part of the night and others just before dawn, or they can take turns to harvest (Birder H;Moller 2002).…”