Part of the trouble with Kalk's questions is the fact that he usually asks multiple questions in the same posting, then provides unsubstantiated opinion. He also appears to be deliberately distorting the numbers that I and others have provided. I have provided replies to some questions, but do not intend to do analyses or research just to suit questions/allegations that are frivolous or derogatory.
As far as the CDT, the methods by which IMA did sampling and CDT testing were explained in the published paper. The sampling was conducted all over the Philippines from collectors at sea, from villages, from distribution sites (e.g., airports), and from export facilities. CDT testing was done at 5 regional laboratories and at the central Manila laboratory. Most samples were obtained by random sampling by species. Some fish were voluntarily submitted by law enforcement officials and by exporters. No fees were charged to the law enforcement agents that submitted samples (for prosecution purposes) or to exporters seeking to determine whether the fish they purchased from collectors or middlemen were tainted with cyanide or not.
In terms of the way I chose to summarize the test results, I realized that it was impossible to present the results in the paper at the species level (although I did tabulate that), or even the genus level because there were 973 species of aquarium fish and food fish in the database. Hence, I chose to summarize the percentages present or absent at the Family level. This makes for larger sample sizes and a better interpretation of the percentages derived from the numbers tested within each family. The numbers tested are important, so I tabulated those numbers. This can help the reader determine how reliable the percentages are.
Admittedly, the numbers of gobies tested is fairly low (79). But it still provides for a minimal sample (>30) that most statisticians find acceptable for this type of tabulation.
As far as how random sampling should be conducted, it is clearly unfeasible to sample a minimum of 30 specimens of every species when one is faced with sampling over 900 species. If damselfish represent say 43% by numbers it does not make sense to sample them in proportion to their abundance, while not sampling enough of the less prevalent species in other families (such as gobies). But, this appears to have occurred to some degree (I did not have any ability to influence the sampling when IMA conducted it). At present there is no sampling (random or otherwise) being conducted by BFAR staff. I have recommended to the MAC that future sampling should ensure that every fish or invertebrate family is sampled on a more equal basis. The random sampling should focus on getting a sample from each family present (random sampling of species within each family) whenever sampling occurs (in the field or at export facilities). This still will not allow very large sample sizes by species; but it will provide a better overview of the use of cyanide by the collectors, and the proportions of fish containing cyanide being exported.
I have not discussed issues such as "suitable species" which should or should not be captured and traded. John Brandt and others have created such lists. One should consult the report created by the World Conservation Monitoring Center (in collaboration with the MAC). Their report is downloadable from their web site.
Peter Rubec
As far as the CDT, the methods by which IMA did sampling and CDT testing were explained in the published paper. The sampling was conducted all over the Philippines from collectors at sea, from villages, from distribution sites (e.g., airports), and from export facilities. CDT testing was done at 5 regional laboratories and at the central Manila laboratory. Most samples were obtained by random sampling by species. Some fish were voluntarily submitted by law enforcement officials and by exporters. No fees were charged to the law enforcement agents that submitted samples (for prosecution purposes) or to exporters seeking to determine whether the fish they purchased from collectors or middlemen were tainted with cyanide or not.
In terms of the way I chose to summarize the test results, I realized that it was impossible to present the results in the paper at the species level (although I did tabulate that), or even the genus level because there were 973 species of aquarium fish and food fish in the database. Hence, I chose to summarize the percentages present or absent at the Family level. This makes for larger sample sizes and a better interpretation of the percentages derived from the numbers tested within each family. The numbers tested are important, so I tabulated those numbers. This can help the reader determine how reliable the percentages are.
Admittedly, the numbers of gobies tested is fairly low (79). But it still provides for a minimal sample (>30) that most statisticians find acceptable for this type of tabulation.
As far as how random sampling should be conducted, it is clearly unfeasible to sample a minimum of 30 specimens of every species when one is faced with sampling over 900 species. If damselfish represent say 43% by numbers it does not make sense to sample them in proportion to their abundance, while not sampling enough of the less prevalent species in other families (such as gobies). But, this appears to have occurred to some degree (I did not have any ability to influence the sampling when IMA conducted it). At present there is no sampling (random or otherwise) being conducted by BFAR staff. I have recommended to the MAC that future sampling should ensure that every fish or invertebrate family is sampled on a more equal basis. The random sampling should focus on getting a sample from each family present (random sampling of species within each family) whenever sampling occurs (in the field or at export facilities). This still will not allow very large sample sizes by species; but it will provide a better overview of the use of cyanide by the collectors, and the proportions of fish containing cyanide being exported.
I have not discussed issues such as "suitable species" which should or should not be captured and traded. John Brandt and others have created such lists. One should consult the report created by the World Conservation Monitoring Center (in collaboration with the MAC). Their report is downloadable from their web site.
Peter Rubec
