FINAL SUMMARY SYNTHESIS AND CONCLUSIONS 



CHARACTERISTICS OF CANYONS 



To best summarize the information presented in a full day's scientific 

 presentations and nearly a full day of roundtable discussions, "information 

 capsules" were prepared on the principal topics that seemed to underlie the 

 conclusions and recommendations of the scientific panel. These capsules 

 follow on the next several pages. 



Submarine Canyons - Special Environments 



Submarine canyons support a higher concentration (numbers, biomass, and 

 diversity) of large, bottom-dwelling animals than adjacent environments on the 

 continental shelf. The high biomass and diversity of commercially important 

 species such as lobsters, crabs, shrimp, flounders, hake, ocean pout, cusk, 

 and tilefish at the heads of canyons is primarily due to the wide variety of 

 substrate types. These substrates provide three-dimensional shelters, 

 including burrows and grottos excavated by the animals. Such shelters are 

 frequently utilized by juveniles, making the canyons important nursery 

 grounds. At greater depths along the canyon axis, and down the walls, are a 

 variety of corals and sponges. Many of these corals and sponges, along with 

 the cleaner shrimp, black-bellied rosefish, and tilefish from the shallow 

 regions of the canyon heads, are found only in canyons. Also, several species 

 that are common on the continental slope, such as brittle stars, long-nosed 

 eels, rattail fish, and sea pens, are found in much higher abundances in 

 canyons. The specific species composition varies from canyon to canyon, 

 probably reflecting physical differences among canyons. The sessile species 

 in the deeper canyon axis may represent an important proportion of the total 

 local population. These stock populations may be necessary for future 



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