Context-dependent effects of a marine ecosystem engineer on predator-prey interactions

In the marine ecosystem, the time delay or lag may occur in the predator response function, which measures the rate of capture of prey by a predator. This is because, when the growth of the prey population is null at the time delay period, the predator’s growth is affected by its population and prey population densities only after the time delay period. Therefore, the generalized Gause type predator-prey fishery models with a selective proportional harvesting rate of fish and time lag in the Holling type II predator response function are proposed to simulate and solve the population dynamical problem. From the mathematical analysis of the models, a certain dimension of time delays in the predator response or reaction function can change originally stable non-trivial critical points to unstable ones. This is due to the existence of the Hopf bifurcation that measures the critical values of the time lag, which will affect the stabilities of the non-trivial critical points of the models. Therefore, the effects of increasing and decreasing the values of selective proportional harvesting rate terms of prey and predator on the stabilities of the non-trivial critical points of the fishery models were analysed. Results have shown that, by increasing the values of the total proportion of prey and predator harvesting denoted by qx Ex and qy Ey respectively, within the range 0.3102 ≤ qx Ex ≤ 0.9984 and 0.5049 ≤ qy Ey ≤ 0.5363, the originally unstable non-trivial critical points of the fishery models can be stable.

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The magnitude of behavioural responses to artificial light at night depends on the ecological context in a coastal marine ecosystem engineer

Marine Environmental Research ◽

10.1016/j.marenvres.2020.105238 ◽

2020 ◽

pp. 105238

Author(s):

J.D. Nuñez ◽

V. Sbragaglia ◽

E.D. Spivak ◽

N. Chiaradia ◽

T.A. Luppi

Keyword(s):

Ecosystem Engineer ◽

Marine Ecosystem ◽

Artificial Light ◽

Ecological Context ◽

Light At Night ◽

Behavioural Responses ◽

Coastal Marine Ecosystem ◽

Coastal Marine

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Growth and longevity of the Antarctic scallop Adamussium colbecki under annual and multiannual sea ice

Antarctic Science ◽

10.1017/s0954102020000322 ◽

2020 ◽

Vol 32 (6) ◽

pp. 466-475

Author(s):

Kelly E. Cronin ◽

Sally E. Walker ◽

Roger Mann ◽

Antonie S. Chute ◽

M. Chase Long ◽

...

Keyword(s):

Sea Ice ◽

Nutrient Availability ◽

Life Histories ◽

Ecosystem Engineer ◽

Marine Ecosystem ◽

Individual Variability ◽

Marine Communities ◽

Antarctic Sea Ice ◽

The Antarctic ◽

Adamussium Colbecki

AbstractEcosystem engineers such as the Antarctic scallop (Adamussium colbecki) shape marine communities. Thus, changes to their lifespan and growth could have far-reaching effects on other organisms. Sea ice is critical to polar marine ecosystem function, attenuating light and thereby affecting nutrient availability. Sea ice could therefore impact longevity and growth in polar bivalves unless temperature is the overriding factor. Here, we compare the longevity and growth of A. colbecki from two Antarctic sites: Explorers Cove and Bay of Sails, which differ by sea-ice cover, but share similar seawater temperatures, the coldest on Earth (-1.97°C). We hypothesize that scallops from the multiannual sea-ice site will have slower growth and greater longevity. We found maximum ages to be similar at both sites (18–19 years). Growth was slower, with higher inter-individual variability, under multiannual sea ice than under annual sea ice, which we attribute to patchier nutrient availability under multiannual sea ice. Contrary to expectations, A. colbecki growth, but not longevity, is affected by sea-ice duration when temperatures are comparable. Recent dramatic reductions in Antarctic sea ice and predicted temperature increases may irrevocably alter the life histories of this ecosystem engineer and other polar organisms.

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Host plasticity supports spread of an aquaculture introduced virus to an ecosystem engineer

Parasites & Vectors ◽

10.1186/s13071-020-04373-y ◽

2020 ◽

Vol 13 (1) ◽

Cited By ~ 1

Author(s):

Babette Bookelaar ◽

Sharon A. Lynch ◽

Sarah C. Culloty

Keyword(s):

Ecosystem Engineer ◽

Marine Ecosystem ◽

Bird Species ◽

Keystone Species ◽

Migratory Bird ◽

Age Cohorts ◽

Top Predators ◽

Ability To Act ◽

Ostreid Herpesvirus 1 ◽

The Impact

Abstract Background The common cockle Cerastoderma edule plays an important ecological role in the marine ecosystem both as an infaunal engineer (reef forming and bioturbation) and a food source for protected bird species in its European range. Cockle beds are found in close proximity to aquaculture and fisheries operations, which can be “hot spots” for infectious agents including viruses and bacteria. Ostreid herpesvirus-1 microVar (OsHV-1 μVar) has spread to many Pacific oyster Crassostrea gigas culture sites globally, where it has been associated with significant mortalities in this cultured bivalve. Knowledge on the impact of the virus on the wider ecosystem, is limited. As the likelihood of released virus dispersing into the wider aquatic ecosystem is high, the plasticity of the virus and the susceptibility of C. edule to act as hosts or carriers is unknown. Methods In this study, wild C. edule were sampled biweekly at two C. gigas culture sites over a four-month period during the summer when OsHV-1 μVar prevalence is at its highest in oysters. C. edule were screened for the virus molecularly (PCR, qPCR and Sanger sequencing) and visually (in situ hybridisation (ISH)). The cockle’s ability to act as a carrier and transmit OsHV-1 μVar to the oyster host at a temperature of 14 ℃, when the virus is considered to be dormant until water temperatures exceed 16 ℃, was also assessed in laboratory transmission trials. Results The results demonstrated that OsHV-1 μVar was detected in all C. edule size/age cohorts, at both culture sites. In the laboratory, viral transmission was effected from cockles to naïve oysters for the first time, five days post-exposure. The laboratory study also demonstrated that OsHV-1 μVar was active and was successfully transmitted from the C. edule at lower temperatures. Conclusions This study demonstrates that OsHV-1 μVar has the plasticity to infect the keystone species C. edule and highlights the possible trophic transmission of the virus from cockles to their mobile top predators. This scenario would have important implications, as a greater geographical range expansion of this significant pathogen via migratory bird species may have an impact on other species that reside in bird habitats most of which are special areas of conservation.

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Local thermal adaptation and limited gene flow constrain future climate responses of a marine ecosystem engineer

Evolutionary Applications ◽

10.1111/eva.12909 ◽

2020 ◽

Vol 13 (5) ◽

pp. 918-934 ◽

Cited By ~ 4

Author(s):

Adam D. Miller ◽

Melinda A. Coleman ◽

Jennifer Clark ◽

Rachael Cook ◽

Zuraya Naga ◽

...

Keyword(s):

Gene Flow ◽

Ecosystem Engineer ◽

Marine Ecosystem ◽

Thermal Adaptation ◽

Future Climate ◽

Limited Gene Flow ◽

Climate Responses

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"Nested" cryptic diversity in a widespread marine ecosystem engineer: a challenge for detecting biological invasions

BMC Evolutionary Biology ◽

10.1186/1471-2148-11-176 ◽

2011 ◽

Vol 11 (1) ◽

Cited By ~ 30

Author(s):

Peter R Teske ◽

Marc Rius ◽

Christopher D McQuaid ◽

Craig A Styan ◽

Maxine P Piggott ◽

...

Keyword(s):

Biological Invasions ◽

Ecosystem Engineer ◽

Marine Ecosystem ◽

Cryptic Diversity

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Size Spectrum Theory

Fish Ecology, Evolution, and Exploitation ◽

10.23943/princeton/9780691192956.003.0002 ◽

2019 ◽

pp. 15-37

Author(s):

Ken H. Andersen

Keyword(s):

Body Size ◽

Power Law ◽

Clearance Rate ◽

Size Structure ◽

Prey Size ◽

Marine Ecosystem ◽

Size Spectrum ◽

Predator Prey ◽

Predation Mortality ◽

Size Preference

This chapter follows the size-structure of the entire marine ecosystem. It shows how the Sheldon spectrum emerges from predator–prey interactions and the limitations that physics and physiology place on individual organisms. How predator–prey interactions and physiological limitations scale with body size are the central assumptions in size spectrum theory. To that end, this chapter first defines body size and size spectrum. Next, it shows how central aspects of individual physiology scale with size: metabolism, clearance rate, and prey size preference. On that basis, it is possible to derive a power-law representation of the size spectrum by considering a balance between the needs of an organism (its metabolism) and the encountered prey, which is determined by the spectrum, the clearance rate, and the size preference. Lastly, the chapter uses the solution of the size spectrum to derive the expected size scaling of predation mortality.

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