scholarly journals Coupling biogeochemical tracers with fish growth reveals physiological and environmental controls on otolith chemistry

2017 ◽  
Vol 87 (3) ◽  
pp. 487-507 ◽  
Author(s):  
Gretchen L. Grammer ◽  
John R. Morrongiello ◽  
Christopher Izzo ◽  
Peter J. Hawthorne ◽  
John F. Middleton ◽  
...  
Keyword(s):  
Fish Growth ◽  
Otolith Chemistry ◽  
Environmental Controls ◽  
Biogeochemical Tracers

scholarly journals Incorporating temporal heterogeneity in environmental conditions into a somatic growth model

2017 ◽  
Vol 74 (3) ◽  
pp. 316-326 ◽  
Author(s):  
M.C. Dzul ◽  
C.B. Yackulic ◽  
J. Korman ◽  
M.D. Yard ◽  
J.D. Muehlbauer
Keyword(s):  
Food Availability ◽  
Growth Model ◽  
Environmental Conditions ◽  
Colorado River ◽  
Growth Models ◽  
Somatic Growth ◽  
Environmental Data ◽  
Fish Growth ◽  
Positive Temperature ◽  
Environmental Controls

Evaluating environmental effects on fish growth can be challenging because environmental conditions may vary at relatively fine temporal scales compared with sampling occasions. Here we develop a Bayesian state-space growth model to evaluate effects of monthly environmental data on growth of fish that are observed less frequently (e.g., from mark–recapture data where time between captures can range from months to years). We assess effects of temperature, turbidity, food availability, flow variability, and trout abundance on subadult humpback chub (Gila cypha) growth in two rivers, the Colorado River (CR) and the Little Colorado River (LCR), and we use out-of-sample prediction to rank competing models. Environmental covariates explained a high proportion of the variation in growth in both rivers; however, the best growth models were river-specific and included either positive temperature and turbidity duration effects (CR) or positive temperature and food availability effects (LCR). Our approach to analyzing environmental controls on growth should be applicable in other systems where environmental data vary over relatively short time scales compared with animal observations.

Disentangling the role of shared ancestry and the environment on leaf stable isotopes

2019 ◽  
Author(s):  
Marko J. Spasojevic ◽  
Sören Weber1
Keyword(s):  
Stable Isotopes ◽  
Environmental Conditions ◽  
Evolutionary History ◽  
Environmental Control ◽  
Phylogenetic Signal ◽  
Individual Species ◽  
Habitat Types ◽  
Δ13c And Δ15n ◽  
Environmental Controls ◽  
Shared Ancestry

Stable carbon (C) and nitrogen (N) isotopes in plants are important indicators of plant water use efficiency and N acquisition strategies. While often regarded as being under environmental control, there is growing evidence that evolutionary history may also shape variation in stable isotope ratios (δ13C and δ15N) among plant species. Here we examined patterns of foliar δ13C and δ15N in alpine tundra for 59 species in 20 plant families. To assess the importance of environmental controls and evolutionary history, we examined if average δ13C and δ15N predictably differed among habitat types, if individual species exhibited intraspecific trait variation (ITV) in δ13C and δ15N, and if there were a significant phylogenetic signal in δ13C and δ15N. We found that variation among habitat types in both δ13C and δ15N mirrored well-known patterns of water and nitrogen limitation. Conversely, we also found that 40% of species exhibited no ITV in δ13C and 35% of species exhibited no ITV in δ15N, suggesting that some species are under stronger evolutionary control. However, we only found a modest signal of phylogenetic conservatism in δ13C and no phylogenetic signal in δ15N suggesting that shared ancestry is a weaker driver of tundra wide variation in stable isotopes. Together, our results suggest that both evolutionary history and local environmental conditions play a role in determining variation in δ13C and δ15N and that considering both factors can help with interpreting isotope patterns in nature and with predicting which species may be able to respond to rapidly changing environmental conditions.

Environmental controls on estuarine nitrifying communities along a salinity gradient

2017 ◽  
Vol 80 (2) ◽  
pp. 167-180 ◽  
Author(s):  
M Monteiro ◽  
J Séneca ◽  
L Torgo ◽  
DFR Cleary ◽  
NCM Gomes ◽  
...  
Keyword(s):  
Salinity Gradient ◽  
Environmental Controls

TOWARDS THE QUESTION OF SPECIALIZED FEEDS FOR TENCHES (TINCA TINCA)

2017 ◽  
pp. 89-97
Author(s):  
Elena Mikhaylovna Chervonenko ◽  
Lina Yurievna Lagutkina
Keyword(s):  
Growth Rate ◽  
Fish Growth ◽  
Animal Origin ◽  
State Technical ◽  
Tinca Tinca ◽  
Daily Growth ◽  
Volga River ◽  
The Moment ◽  
First Time ◽  
Technical Centre

The article describes the process of tench growing (male and female species removed from set gear in the Volga river in the Astrakhan region) using experimental feedstuff "T", taking into account the fact that problems with artificial growing tench ( Тinca tinca ) appear first in the process of feeding when wild sires change to artificial food. The research took place on the base of the department of aquaculture and water bioresources of Astrakhan State Technical University in innovation centre "Bioaquapark - scientific and technical centre of aquaculture" in 2015. Special feed including components of animal origin - mosquito grab and sludge worm as an effective substitute to fish flour, as well as components of vegetable origin (carrot, parsley, pumpkin, wheatgrass) for domestication of tenches are offered for the first time. Food technology has been described. The exact composition of the formula, which is being licensed at the moment, is not disclosed. Feed "T", which has undergone biological analysis and is in accordance with organoleptic and physical standards was used for feeding tench female and male species during domestication period (60 days), along with food "Coppens" (Holland). Feed efficiency was determined according to survival and daily fish growth. Growth rate of females appeared more intensive than growth rate of males fed with experimental food "T". Daily growth changed depending on the types of food: from 0.3 ("Coppens") to 0.47 (experimental food) in females, from 0.25 ("Coppens") to 0.39 (experimental food) with males. Ability to survive among tench species fed with "Coppens" and experimental food made 60% and 100%, correspondingly. Nutricion of tench species with experimental food encouraged their domestication, which allowed using tench species in further fish breeding process in order to get offspring. The project was supported by the Innovation Promotion Fund in terms of the project "Development and implementation of the technique for the steady development of aquaculture: food "TechSA".

Features of spring feeding of sterlet of the middle course of the Northern Dvina river

2020 ◽  
pp. 8-17
Author(s):  
A. Bykov ◽  
D. Palatov ◽  
I. Studenov ◽  
D. Chupov
Keyword(s):  
Benthic Communities ◽  
High Water ◽  
Food Composition ◽  
Fish Growth ◽  
High Water Content ◽  
Feeding Intensity ◽  
Biting Midges ◽  
Size Groups ◽  
Main Components ◽  
A Minor

The article provides information about the features of spring feeding of sterlet in the spawning grounds of the middle course of the Northern Dvina river in may 2019. The main and secondary groups of forage objects in the diet of this species of sturgeon are characterized. The article considers the variability of the sterlet food composition with an increase in the size of fish from 30 to 60 cm. In the process of fish growth in the diet of the Severodvinsk sterlet, the main components in terms of occurrence and mass in all size groups are the larvae of Brooks and chironomids. A minor occurrence was the larvae of midges, biting midges, stoneflies, mayflies and small clams. To random and seasonal food are the larvae of water bugs, butterflies, flies, beetles and eggs of other fish. The feeding intensity of the smaller sterlet (30–40 cm) was significantly higher than that of the fish in the size groups 40–50 and 50–60 cm. Fundamental changes in the diet of the Severodvinsk sterlet for the main food objects for more than sixty years of observations have not been established. During periods of high water content of the Northern Dvina due to seasonal changes in the structure of benthic communities, the value of Brooks in the diet of sterlet increases and the proportion of chironomids decreases.

Sign in / Sign up

Export Citation Format

Share Document