Long-term decline in the calanoid copepod Acartia tonsa in central Chesapeake Bay, USA: An indirect effect of eutrophication?

Long-term (20032014) routine observations of zooplankton in Sevastopol Bay (the Black Sea) have allowed the naturalization of the invasive copepod Oithona davisae to be studied in the Black Sea coastal waters. Inter-annual and seasonal variability of the species and their impact on the native copepod community have been analyzed. The invasion of O. davisae and their undoubted dominance in terms of abundance were shown to alter the community structure but, at the same time, the abundances of the native species did not decrease, excepting the Black Sea earlier invader Acartia tonsa. A significant decline in A. tonsa numbers over the stages of O. davisae establishment and naturalization provided evidence of competition between the species. O. davisae have been demonstrated to gain competitive advantage over A. tonsa, that ensured their fast dispersal in the Black Sea, acclimatization in the new habitat and the successful competition over native species.

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Chesapeake Bay Stock Assessment: Who are they, and Where are they?

Water Science & Technology ◽

10.2166/wst.1992.0371 ◽

1992 ◽

Vol 26 (12) ◽

pp. 2705-2709 ◽

Cited By ~ 1

Author(s):

H. M. Austin

Keyword(s):

Chesapeake Bay ◽

Stock Assessment ◽

Human Consumption ◽

Population Fluctuations ◽

Important Species ◽

Fisheries Resources ◽

Environmentally Sensitive ◽

Climate Scale ◽

Resource And Environment

The Chesapeake Bay, while a significant habitat for fisheries resources, is in actuality an aquatic “bedroom community”, as many of the economically important species are seasonally transient. The pressure on these resources due to their demand for human consumption and recreation, proximity to extensive industrial activity along the shores, and climate scale environmental fluctuations has resulted in stock declines by most important species. Our inability to separate natural population fluctuations from those of anthropogenic origin complicates management efforts. The only way to make these separations, and subsequent informed management decisions is by supporting long-term stock assessment programs (monitoring) in the Bay which allow us to examine trends, cycles and stochastic processes between resource and environment. These programs need to monitor both recruitment and fishing mortality rates of the economically important species, and to identify and monitor the environmentally sensitive “canary” species.

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Predation by gelatinous zooplankton and resource limitation as potential controls of Acartia tonsa copepod populations in Chesapeake Bay

Limnology and Oceanography ◽

10.4319/lo.1994.39.2.0263 ◽

1994 ◽

Vol 39 (2) ◽

pp. 263-278 ◽

Cited By ~ 55

Author(s):

Jennifer E. Purcell ◽

Jacques R. White ◽

Michael R. Roman

Keyword(s):

Chesapeake Bay ◽

Resource Limitation ◽

Gelatinous Zooplankton ◽

Acartia Tonsa

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Long-term seasonal trends of nitrogen, phosphorus, and suspended sediment load from the non-tidal Susquehanna River Basin to Chesapeake Bay

The Science of The Total Environment ◽

10.1016/j.scitotenv.2013.02.012 ◽

2013 ◽

Vol 452-453 ◽

pp. 208-221 ◽

Cited By ~ 38

Author(s):

Q. Zhang ◽

D.C. Brady ◽

W.P. Ball

Keyword(s):

Chesapeake Bay ◽

Suspended Sediment ◽

River Basin ◽

Sediment Load ◽

Suspended Sediment Load ◽

Seasonal Trends ◽

Susquehanna River ◽

Susquehanna River Basin ◽

Nitrogen Phosphorus

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Can we predict the future: juvenile finfish and their seagrass nurseries in the Chesapeake Bay

ICES Journal of Marine Science ◽

10.1093/icesjms/fst142 ◽

2013 ◽

Vol 71 (3) ◽

pp. 681-688 ◽

Cited By ~ 6

Author(s):

Cynthia M. Jones

Keyword(s):

Climate Change ◽

Chesapeake Bay ◽

Juvenile Fish ◽

Single Species ◽

Potential Effect ◽

Seagrass Habitat ◽

Important Conclusion ◽

The Relationship ◽

Landscape Level

Abstract The importance of estuarine seagrass beds as nurseries for juvenile fish has become a universal paradigm, especially for estuaries that are as important as the Chesapeake Bay. Yet, scientific tests of this hypothesis were equivocal depending on species, location, and metrics. Moreover, seagrasses themselves are under threat and one-third of seagrasses have disappeared worldwide with 65% of their losses occurring in estuaries. Although there have been extensive studies of seagrasses in the Chesapeake Bay, surprisingly few studies have quantified the relationship between seagrass as nurseries for finfish in the Bay. Of the few studies that have directly evaluated the use of seagrass nurseries, most have concentrated on single species or were of short duration. Few landscape-level or long-term studies have examined this relationship in the Bay or explored the potential effect of climate change. This review paper summarizes the seagrass habitat value as nurseries and presents recent juvenile fish studies that address the dearth of research at the long term and landscape level with an emphasis on the Chesapeake Bay. An important conclusion upon the review of these studies is that predicting the effects of climate change on fishery production remains uncertain.

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