Those wishing to collect seaweed on the field trip, not just observe, must purchase a shellfish/seaweed recreational license from the Washington Department of Fish and Wildlife. Looking and photos are free!
Fees are found at: https://fishhunt.dfw.wa.gov/wdfw/licenses_fees.html
Licenses can be purchased on-line at: https://fishhunt.dfw.wa.gov/wdfw/oc_system/index.html
Regulations are in the pamphlet at: http://wdfw.wa.gov/fish/regs/2009/2009sportregs.pdf. Seaweed info is on p. 129.
In a nutshell, resident 1-day licenses costs $8.18 +$2 fee, non-resident license is $15.82+$2 fee
Maximum collection amount is 10 pounds wet per day.