Diel vertical migration in the Lake Superior pelagic community. II. Modeling trade-offs at an intermediate trophic level

2006 ◽  
Vol 63 (10) ◽  
pp. 2296-2307 ◽  
Author(s):  
Olaf P Jensen ◽  
Thomas R Hrabik ◽  
Steven J.D. Martell ◽  
Carl J Walters ◽  
James F Kitchell

Several hypotheses have been proposed to explain diel vertical migration (DVM); however, they have generally been applied to DVM behavior of a single trophic level. We evaluate the costs (predation risk) and benefits (foraging rate and growth rate potential) of different hypothetical and observed DVM trajectories for a three-level pelagic food chain in Lake Superior containing opossum shrimp (Mysis relicta), deepwater ciscoes (Coregonus spp.), and lake trout (Salvelinus namaycush). Lake trout appear to be maximizing foraging and growth rates by tracking vertically migrating ciscoes, while the DVM trajectories of ciscoes suggests a trade-off between predation risk and growth. For ciscoes, two alternative DVM trajectories both minimize the ratio of risk to growth: a shallow trajectory that follows low light levels down to 80 m during the day and a deep trajectory (below 150 m) that tracks highest Mysis densities. Observed cisco DVM trajectories appear to follow the shallow high risk – high growth trajectory in 2001, but switch to the deep, low risk – low growth trajectory in 2004 when lake trout density was higher and the density of ciscoes was lower.

2010 ◽  
Vol 67 (3) ◽  
pp. 473-485 ◽  
Author(s):  
Jason D. Stockwell ◽  
Thomas R. Hrabik ◽  
Olaf P. Jensen ◽  
Daniel L. Yule ◽  
Matthew Balge

Recent studies on Lake Superior suggest that diel vertical migration (DVM) of prey (generalized Coregonus spp.) may be influenced by the density of predatory siscowet ( Salvelinus namaycush ). We empirically evaluated this hypothesis using data from acoustic, midwater trawl, and bottom trawl sampling at eight Lake Superior sites during three seasons in 2005 and a subset of sites in 2006. We expected the larger-bodied cisco ( Coregonus artedi ) to exhibit a shallower DVM compared with the smaller-bodied kiyi ( Coregonus kiyi ). Although DVM of kiyi and cisco were consistent with expectations of DVM as a size-dependent, predator-mediated process, we found no relationship between siscowet density and the magnitude of DVM of either coregonid. Cisco appear to have a size refuge from siscowet predation. Kiyi and siscowet co-occur in demersal habitat > 150 m during the day, where visual predation is unlikely, suggesting predator avoidance is not a factor in the daytime distribution of kiyi. Seasonal patterns of kiyi DVM were consistent with reported DVM of their primary prey Mysis relicta . Our results suggest that consideration of nonvisual foraging, rather than light-based foraging theory (i.e., the antipredation window), is necessary to understand the processes driving DVM in deepwater systems.


1999 ◽  
Vol 56 (2) ◽  
pp. 311-322 ◽  
Author(s):  
Gideon Gal ◽  
Ellis R Loew ◽  
Lars G Rudstam ◽  
Ali M Mohammadian

Ambient light levels determine the extent of diel vertical migration of many species including mysid shrimps. Light levels perceived by an organism depend on the intensity of light at the surface, the extinction of light through the water, and the sensitivity of the organism's light receptors. Each of these processes has spectral characteristics that should be taken into account when measuring perceived light levels. We used microspectrophotometry to determine that Mysis relicta has a single pigment with the characteristics of rhodopsin based on vitamin A1 and a peak sensitivity of 520 nm. Similar to the use of the lux (scaled to human vision), we give ambient light levels scaled to the mysid's visual spectrum in mylux units. Mysid distributions were observed with acoustics around two artificial light sources in Cayuga Lake, New York. Mysids avoided light levels of 3.4 × 10-7 to 2.1 × 10-6 mylux. Similar light levels limited their vertical distributions during the night in Lake Ontario and during the day in Cayuga Lake. Of standard light sensors available, lux meters are more appropriate than photosynthetically active radiation meters for determining light levels perceived by mysids.


2013 ◽  
Vol 71 (4) ◽  
pp. 909-917 ◽  
Author(s):  
Christian Jørgensen ◽  
Anders Frugård Opdal ◽  
Øyvind Fiksen

Abstract Since the classical works by Hjort linked the survival of early life stages of fish to year-class strength and recruitment, fisheries science has struggled to understand the fate of fish eggs and larvae. Here we discuss how food availability will influence growth and survival of larvae when foraging behaviour is flexible and involves predation risk. We use theory to show that small larval fish with a high risk of predation should nevertheless forage intensely and maintain high growth rates. The implication of this is that food availability is more important to recruitment success than is often assumed from studies of growth rate, since the main effect of low food availability appears as increased predation rates. As larvae develop and grow bigger, they are expected to tailor their behaviour to balance food intake and predation risk, which makes it more probable that environmental fluctuations will cause growth differences. A theoretical framework including larval behaviour thus illustrates how several existing hypotheses, i.e. “bigger is better”, “stage duration”, and “growth-selective predation”, emphasize different aspects of larval success but can be understood more generally and coherently when interpreted in the light of behavioural trade-offs. This may lead to more consistent consideration of larval behaviour in biophysical models of fish recruitment.


Hydrobiologia ◽  
2008 ◽  
Vol 614 (1) ◽  
pp. 321-327 ◽  
Author(s):  
Meryem Beklioglu ◽  
Ayse Gul Gozen ◽  
Feriha Yıldırım ◽  
Pelin Zorlu ◽  
Sertac Onde

2000 ◽  
Vol 57 (S3) ◽  
pp. 38-50 ◽  
Author(s):  
Geraint Tarling ◽  
Michael Burrows ◽  
Jack Matthews ◽  
Reinhard Saborowski ◽  
Friedrich Buchholz ◽  
...  

An optimisation model was developed to examine the effect of predation risk and environmental conditions on the diel vertical migration (DVM) of adult northern krill (Meganyctiphanes norvegica). Model predictions were compared in two locations with contrasting environmental conditions, the Clyde Sea and the Kattegat. The model was constructed from a combination of parameterised functions and empirical field data obtained during summer conditions. Parameter matrices were set up to cover the entire water column over a 24-h period. The first matrix contained values for "net energy gain," which incorporated empirical data on temperature-dependent respiration, copepod and phytoplankton abundance, and a functional response model for feeding rate. The second matrix expressed the risk of encountering a generalised visual (fish) predator as a function of light levels. The optimisation procedure sought a path through depth and time such that the energy gain was equal to the amount necessary to grow, produce eggs, and moult, while the risk of predation was minimised. The model predicted DVM in both the Clyde Sea and the Kattegat. Sensitivity analyses showed that the predicted DVM pattern was mainly driven by food and predation risk, with temperature effects on metabolic costs having a minor effect.


2006 ◽  
Vol 63 (10) ◽  
pp. 2286-2295 ◽  
Author(s):  
Thomas R Hrabik ◽  
Olaf P Jensen ◽  
Steven J.D. Martell ◽  
Carl J Walters ◽  
James F Kitchell

The distribution of fishes is influenced by a host of physico-chemical and biological variables, including temperature and oxygen, prey abundance, feeding or assimilation rates, and predation risk. We used hydroacoustics and midwater trawls to measure the vertical distribution of pelagic fishes during a series of research cruises on Lake Superior's western arm in 2001 and 2004. Our objective was to assess vertical structuring in the fish assemblage over varying light levels. We observed variability in vertical structuring of both ciscoes (Coregonus spp.) and their primary predator, the siscowet (Salvelinus namaycush siscowet). Our results indicate that deepwater predators and prey migrate extensively over a diel cycle. This migration pattern is most consistent with changes in the distribution of prey resources for siscowet and diel variability in predation risk controlled by changing light levels for ciscoes. The magnitude of vertical migration in ciscoes increased with higher abundance of siscowets, supporting predation risk as a driver of cisco distribution. This study describes the extent of vertical migration in each group of fish, provides a statistical description of the pattern, and discusses the implications for trophic interactions in the Lake Superior food web.


1991 ◽  
Vol 48 (1) ◽  
pp. 67-72 ◽  
Author(s):  
David A. Levy

Dual-beam acoustic surveys of Okanagan Lake suggested active diel vertical migrations of Mysis relicta and kokanee (Oncorhynchus nerka) within the pelagic zone. Mysis relicta were situated between 90–150 m during the day and migrated upwards into the thermocline region of the water column at night. Two groups of kokanee targets were detected. The first undertook a diel vertical migration and coalesced at dusk with a second, shallow-oriented group of targets. Daytime target strength estimates taken while the two groups were vertically segregated in the water column suggested an 8–12 db lower target strength of the deeper group. The results provide acoustic evidence for a smaller body size in the deeper group and the occurrence of an ontogenetic shift in diel migratory behavior of kokanee within Okanagan Lake. Diel comparisons of depth distribution suggested spatial segregation of Mysis and kokanee over much of the diel cycle.


Sign in / Sign up

Export Citation Format

Share Document