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Fishery Bulletin 105(2) 



We appreciate that using linear interpolation of per 

 capita catch rates between anchor points (particularly 

 if widely spaced in time) may introduce additional 

 data uncertainties associated with potential behav- 

 ioral (changes in lifestyle and dietary preferences) and 

 socioeconomic (move towards cash-economy) changes 

 in the human population over that time period. This 

 uncertainty in turn may lead to over- or underes- 

 timation of catches for a given year, for the period 

 between anchor points. However, given the bounds 

 provided by the anchor point data, such uncertainties 

 would primarily influence the shape of the resultant 

 catch curve for the period between each set of anchor 

 points. Given the paucity of other supportive data, the 

 only reliable alternative approach would have been a 

 simple linear interpolation of catches between anchor 

 points. On closer examination of our reconstructed 

 data (see Fig. 2, the source of present data [Zeller et 

 al.^], and Zeller et al., 2006a), such linear interpola- 

 tion would only result in relatively small differences 

 compared to our present approach. For example, a 

 simple linear interpolation of anchor point catches 

 would have smoothed the slight rise in reconstructed 

 catches for CNMI between 1950 and 1980 (Fig. 2C). 

 Overall, however, the broad conclusions and general 

 trends observed here would not have been substan- 

 tially affected. 



The area catch rates as estimated here indicate catch 

 rates ranging from 0.4 to 4.7 t/km'-/year. These esti- 

 mates are all at or near the lower end of the only other 

 comprehensive range of estimates (0.3-64 t/km-/year) 

 established for the Pacific region (Dalzell and Adams, 

 1997). However, all area catch rates are heavily influ- 

 enced by the definition of coral reef area, which here 

 was taken as depth defined (100 fathoms=183 m) poten- 

 tial coral reef ecosystem habitat as defined by Rohmann 

 et al. (2005), which may represent overestimates of true 

 coral reef habitats around each island. Nevertheless, 

 the present estimates indicate that our reconstructed 

 catch estimates, even for the early years, may likely be 

 feasible in a broader ecological context. 



Although the overall finding of our study was that 

 of declining total catches, such declining catches may 

 not necessarily be the result of excessive fishing alone 

 because other factors may also contribute to the decline. 

 These include changes in lifestyles, cash incomes, and 

 dietary preferences of the local populations (as indicated 

 above), as well as habitat degradation and pollution re- 

 sulting from environmentally insensitive developments 

 (Friedlander and DeMartini, 2002). All these factors 

 can potentially lead to declines in the size of fish stocks 

 and catches. Nevertheless, our results do indicate likely 

 substantial changes over the last 50+ years in fisheries 

 catches and should form important baselines for a move 

 towards ecosystem-based resource and habitat manage- 

 ment in the U.S. western Pacific region, particularly 

 as other lines of evidence (e.g., declines in mean size 

 of fish) also indicate that overfishing or stock declines 

 may indeed be occurring in many areas (e.g., Craig et 

 al., 1993). 



Finally, and in our opinion significantly, we suggest 

 strongly that all responsible agencies should be required 

 to implement and maintain regular estimation proce- 

 dures to account for and report all catches taken by all 

 fisheries sectors. According to the data from the present 

 study, Guam may offer a good example and starting 

 point for such considerations. Guam has established 

 an active commitment to creel surveys during the last 

 20-1- years as a mechanism to estimate total catches. 

 It is to be hoped that this commitment will continue. 

 Given the high costs of creel surveys (which are the 

 most suitable method for estimating highly dispersed 

 and de-centralized noncommercial fisheries), resource- 

 limited developing countries should give considerations 

 to regular, albeit nonannual surveys for estimation of 

 noncommercial catches. Well executed and comprehen- 

 sive noncommercial catch estimates undertaken every 

 2-5 years are better than the current scenario of virtu- 

 ally no data collection. 



Management agencies and policy makers should con- 

 sider the distinctly different baselines of past catches 

 as presented in this study, as they shed new light on 

 issues and concerns for fisheries sustainability and eco- 

 system conservation. Furthermore, re-estimations, as 

 presented here, illustrate the importance of small-scale 

 and noncommercial fisheries sectors and indicate a need 

 to account for all fisheries catches in official statistics. 



Acknowledgments 



We thank the Western Pacific Regional Fishery Manage- 

 ment Council for funding the present study. The data 

 provided by D. Hamm from the Western Pacific Fishery 

 Information Network (WPacFIN) at the Pacific Islands 

 Fishery Science Centre, NMFS, NOAA, are greatly appre- 

 ciated. Critical comments by R. Clarke, E. DeMartini, D. 

 Fenner, T. Graham, D. Hamm, K. Lowe, and W. Walsh 

 contributed significantly to this study and are greatly 

 appreciated. The statements, findings, conclusions, and 

 recommendations are those of the authors and do not 

 necessarily reflect the views of NOAA, Guam DAWR, 

 American Samoa DMWR, or CNMI DFW. D. Zeller, S. 

 Booth and D. Pauly acknowledge the support of the Pew 

 Charitable Trusts for funding the Sea Around Us project 

 at the University of British Columbia Fisheries Centre. 



Literature cited 



Craig, P., B. Ponwith, F. Aitaoto, and D. Hamm. 



1993. The commercial, subsistence, and recreational 

 fisheries of American Samoa. Mar. Fish. Rev. 55: 

 109-116. 

 Craig, P., J. H. Choat, L. IVI. Axe, and S. Saucerman. 



1997. Population biology and harvest of the coral reef 

 surgeonfish Acanthurus lineatus in American Samoa. 

 Fish. Bull, 95:680-693. 

 Dalzell, P., T. J. H. Adams, and N. V. C. Polunin. 



1996. Coastal fisheries in the pacific islands. Oceanogr. 

 Mar. Biol. Ann. Rev. 34:395-531. 



