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
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