The Molting Process in Golden King

Dan Urban, NMFS Kodiak Lab Andrew Nault, Alaska Dept. of Fish & Game Golden King Crab Survey Locations

National Marine Fisheries Service, 1983-2016

-1,000m 546 fms

* Surveys only down to ~1,000m * Approx. 40,000 hauls with GKC Golden King Crab Fishery

Not showing 130 stat-areas where catch was confidential (less than 3 vessels or processors) / Fishery Value

Bering Sea Aleutian Other Halibut & S. Tanner GKC Sablefish $194 $25 Salmon $39 $194 $601 Bristol Bay Cod Red KC $213 Bering Sea $78 Snow Crab Pollock $124 $272 $466

Source: McDowell Group 2015 Source: REFM, Alaska Fish. Sci. Ctr. 2016

4 Golden King Crab Phylum Arthropoda

5 Golden King Crab Taxonomy Phylum Arthropoda

6 Golden King Crab Taxonomy Phylum Arthropoda

Alaskan Commercial

Red King crab Northern (pink) Snow crab Blue King crab Sidestripe shrimp Southern Tanner crab Golden King crab Spot shrimp 7 Golden King Crab Taxonomy Phylum Arthropoda

Alaskan Commercial Crustaceans

Red King crab Northern (pink) Shrimp Snow crab Blue King crab Sidestripe shrimp Tanner crab Golden King crab Spot shrimp 8 Molting Process

Four Major Molt Stages (Drach 1939)

PREMOLT MOLTING POSTMOLT INTERMOLT Swollen The process Shell hardening, Shell hardening, abdomen of molting other changes other changes

postmolt intermolt premolt molting 9 Why study the molting process?

Legal crab = last year’s surviving legals + new legals

Sublegal crab that Proportion New Legal = molt to legal-size X that molt

Bristol Bay RKC model, SAFE 2016

10 Golden King Crab Molting

*Molting of adults considered asynchronous (Somerton & Otto 1986)

*In lab setting (58 males, 5-6 inches CL), there was a molting period. Golden King Crab Molting

Andy: KL holding setup

movie Acknowledgements

*F/V Atlantico

*Alaska Department of Fish & Game

*NMFS Staff at the Kodiak Lab.

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15 Golden King Crab Molting

*Molting considered asynchronous (Somerton & Otto 1986)

*Data from fisheries observers and holding studies at the NMFS Kodiak

Lab.

*GKC were held at the KL as part of a tagging study • What was known about GKC molting?

*references: Otto & Cummiskey, AJ Paul, etc. *NMFS AI survey *ADF&G surveys, tagging *synchronous molting events video 18