Mud Shrimp Upogebia pugettensis gigas Ghost shrimp Neotrypaea

Mud Shrimp (Upogebia pugettensis) gigas Ghost shrimp (Neotrypaea californiensis)

Ghost or Sand Shrimp Neotrypaea californiensis - Found in upper intertidal to subtidal zones - Predominantly in sandy sediments - Burrows typically 50 cm depth, but can be > 1 meter - Deposit feeder (detritus, organic particles associated with sediment) - Can occur at densities >400 per sq. meter Volcano-shaped burrow mounds & burrow openings Burrows have 2+ openings many chambers

Mud Shrimp Upogebia pugettensis - Found in mid intertidal to subtidal zones - Predominantly in muddy sediments - Burrows typically 75 cm depth, but can be >1 meter - Filter feeder (plankton, detritus in water) and deposit feeder/ farmer? - Can occur at densities >400 per sq. meter Mud shrimp burrows are typically Y-shaped with 2+ openings. Yaquina Bay tide flat showing mud shrimp burrow openings

Impacts of Burrowing Behavior 1) Burrow Excavation, Deposit Feeding, Defecation = Bioturbation 2) Burrow Ventilation (oxygen exchange) = Bioirrigation Water movement Sediment movement Excavation mounds Burrow Courtesy of Bret Dumbauld

Impact on Carbon & Nutrients Oxygenated water Plankton, detritus Oxygen, organic matter Dissolved nutrients, CO 2 Decomposition solid C, N ® dissolved C, N Dissolved nutrients (N) CO 2

What else lives in these burrows? Pea crabs (3 species) Phoronida (sticks it’s tentacles into the burrow) Copepod (parasitic) Gobi fish (as a refuge) Bivalves (>2 species) Parasitic isopods (at least 2 species) Snapping shrimp (3 species) Scale worms

Orthione griffenis Markham 2004 THE PARASITE FROM HELL!!!! (OR AT LEAST, ASIA)

Earliest occurrence confirmed in Asia Japan 1995: China 1950 s North America since 1988

Ballast water: a likely dispersal mechanism Epicarids, microniscids and cryptoniscids in ballast water from 21 of 129 ships surveyed, Coos Bay, Oregon, in the 1990 s

Oops! Prevalence of Orthione griffenis and density of Upogebia at Cedar River, Site 1988 -2005 (Dumbauld, 2011 ).

Estimated Shrimp Numbers, Yaquina Bay 2002 2008 Total % yr-1 Upo 313, 973, 877 108, 433, 069 65% - 18% Neo 76, 809, 568 83% - 30% 13, 278, 116

Parasite Population Level Effects on Upogebia 20% Infested % Overall Natality Uninfested 15% 10% 68% loss 5% 0% 18 23 28 CL (mm) 33

What’s with the Ghost Shrimp (Neotrypaea) ? 10 July Immigration before and after the solstice

Ocean or Estuary Limits? Both species are estuary limited – Upogebia • • High parasite (Orthione) prevalence Variable ocean survival Early recruitment (< 21 June) Low estuarine post-larval mortality – Neotrypaea • • Low parasite (Ione) prevalence Variable ocean survival Late recruitment (> 21 June) High estuarine post-larval mortality