A rapid intertidal megafauna survey method applied to Upogebia pugettensis, and its introduced parasite, Orthione griffensis

Abstract

A B S T R A C TDeclines or extinctions of the native northeast Pacific intertidal blue mud shrimp, Upogebia pugettensis (Dana, 1852), over the species range are directly associated with intense infestations by the introduced Asian bopyrid isopod parasite, Orthione griffenis Markham, 2004. Single point sampling sites and anecdotal records poorly resolve how this interaction occurs within estuaries and among geographical regions. This broad scale interaction can only be resolved at the meta-population scales over which they occur but the surveys needed for this research are proceeding slowly or, in most cases, have not begun. The large efforts and major field and computational resources that grid or random point surveys employed for this work to date have proven to be major obstacles. We therefore tested a new method in Alsea Bay, Oregon, in which shrimp bed perimeters and areas are algebraically defined previous to direct sampling within predefined population areas. This new method is intuitive, reduces logistics, greatly reduces field and computational resources and produces equally useful results to previous survey methods. The Alsea Bay populations of U. pugettensis surveyed by these new methods are sufficiently abundant to remain "ecosystem engineers." However, intense infestations of their populations by Orthione cause significant reproductive losses. The Alsea Bay population appears to be declining along with all other known U. pugettensis in Oregon estuaries. -1980s (Dumbauld, 2011Chapman et al., 2012). All known populations of Upogebia are intensely infested by Orthione, which effectively castrate their female hosts (Smith et al., 2008;Chapman et al., 2012). All populations of Upogebia between Vancouver, British Columbia and Morro Bay, California appear to be declining (Chapman et al., 2012). The nature of Orthione's virulence and its effects on Upogebia-populations are unexpected and poorly known. Upogebia are the only host of Orthione north of Morro Bay (Chapman et al., 2012). Recruitment of such single host parasites normally decline when their only available hosts decline (O'Keefe and Antonovics, 2002;Deredec and Courchamp, 2003). Orthione prevalence, however, does not decline with abundances of Upogebia (Dumbauld * Corresponding author; e-mail: john.chapman@oregonstate.edu Chapman et al., 2012). Moreover, Orthione produce multiple broods and appear to survive past the reproductive competence of their host populations (Chapman et al., 2012). The nonindigenous origins of Orthione in North America and the absence of refuges for its new hosts preclude assumptions of the hosts' resilience, equilibrium domains or otherwise long-term persistence (Chapman et al., 2012). Understanding how this interaction occurs is therefore critical for any conservation efforts. Emerging questions that cannot be addressed from existing information include: whether Upogebia have refuges or variable population structures within or among estuaries, the magnitudes of local and coast-wide extinctions and population declines, wh...

Life History and Production of the Western Gray Whale’s Prey, Ampelisca eschrichtii Krøyer, 1842 (Amphipoda, Ampeliscidae)

“…eschrichtii Complex IV sampling sites and WGW foraging ( Fig 1 ) by the field perimeters 2011 WGW sightings in 2011 [ 25 ]. We estimated the overlapping areas of these perimeters by polygon triangles summation using their geographical coordinates [ 59 ]. We produced all maps using open source software QGIS v. 2.12.1-Lyon ( http://qgis.org/ru/site/ ).…”

Population Characteristics of the Mud Shrimp Upogebia major (De Haan, 1841) (Decapoda: Gebiidea: Upogebiidae) on Korean Tidal Flats in the Eastern Yellow Sea

“…They are considered among the most influential ecosystem engineers in marine soft-bottom ecosystems [6,[10][11][12][13]. Their burrows not only expand into the sediment surface areas of estuaries and supply oxygenated water deep into subsurface sediments [14][15][16][17], but they also become microhabitats for various benthic animals and influence the structure of benthic communities in these habitats [18][19][20][21][22][23][24][25][26]. Additionally, their filter feeding improves water quality by capturing suspended particles, which in turn affects the coastal ecosystem and serves a vital ecological function [11,[27][28][29][30][31][32].…”

“…However, recently, this mud shrimp has mostly disappeared [36]. Dramatic declines in this native northeast Pacific mud shrimp over the past three decades have occurred in response to intense infestations by the Asian bopyrid isopod parasite, Orthione griffenis Markham, 2004 introduced in the 1980s [17,[36][37][38][39][40][41][42][43]. Making matters worse, the recent taxonomic review of Upogebia revealed a previously reported 1912 invasion of San Francisco Bay by Upogebia affinis (Say, 1818) that was in error; hence, the introduction of U. major is the first confirmed gebiid invasion in the world.…”

Parasites (Isopoda: Epicaridea and Nematoda) from ghost and mud shrimp (Decapoda: Axiidea and Gebiidea) with descriptions of a new genus and a new species of bopyrid isopod and clarification of Pseudione Kossmann, 1881

“…Mud shrimps are also host to the only documented case of an introduced epicaridean parasite Chapman et al 2012;Hong et al 2015). This parasite, Orthione griffenis Markham, 2004, has had profound impacts on populations of their ecosystem engineer hosts (Chapman & Carter 2014).…”