Ocean Sciences in Relation to Living Resources

1982 ◽  
Vol 39 (7) ◽  
pp. 1059-1070 ◽  
Author(s):  
Andrew Bakun ◽  
Jan Beyer ◽  
Daniel Pauly ◽  
John G. Pope ◽  
Gary D. Sharp

The Intergovernmental Oceanographic Commission's Resolution XI-17 on Ocean Sciences in Support of Living Resources specifies that programs should be formulated in applied ocean research related to fishery problems. In this report we identify some types of needed research. We discuss the relative importance of the various life history stages to the question of resource variation regarding difficulties in sampling or studying on relevant scales. Our report stresses identification and accounting for causal climate-driven ambient variations. Some testable hypotheses relating the larval stages are given as examples of useful research. We also describe research needed on predation and species interactions. Examples of specific systems where important ecological processes need intense study are given. Upwelling areas, coral reefs, tropical and shelf demersal fisheries, and the open ocean fisheries each require different types and scales of study. The importance of data accessability and multidisciplinary research activities, beginning with dialogues between the ocean research and fishery resource scientists is paramount to successful completion of these tasks. The examples provided may stimulate further effort to identify resource research problems and programs for resolving them.Key words: ocean science, living resources, life history cycles, fishery recruitment, predation, species interactions, fish eggs and larvae, vertical stability of the ocean, advection, convergence and divergence, upwelling systems, coral reefs, tropical demersal fisheries

2021 ◽  
Vol 20 (01) ◽  
pp. C09
Author(s):  
Ana Claudia Nepote ◽  
Pedro Medina-Rosas

Despite Mexico has coasts in the Pacific and Atlantic oceans, people's connection towards the sea and marine environments is quite poor. Our commentary focuses on Mexico's coral reefs, relevant tropical ecosystems to human and oceanic welfare, and it emerges from the experience of the production of an itinerant coral reefs exhibit in Mexico, committed to the conservation and awareness of this threatened habitat. The UN Decade of Ocean Science for Sustainable Development starts in 2021 and represents an opportunity to increase initiatives for public communication of science on marine and oceanic issues in Mexico and the world.


2024 ◽  
Vol 74 (10) ◽  
pp. 6139-2024
Author(s):  
MICHAŁ SCHULZ ◽  
ALEKSANDRA ŁOŚ ◽  
PATRYCJA SKOWRONEK ◽  
ANETA STRACHECKA

Coral reefs are the most productive ecosystems on Earth. They ensure the conservation of biodiversity and are a live habitat for 25% of all marine organisms. The main relationship on the coral reef is the symbiosis between corals and algae from the genus Symbiodinium (commonly called zooxanthellae). The authors of this publication have characterized and described the factors limiting the occurrence of coral reefs, including: water temperature, salinity, access to sunlight, contamination, physicochemical and hydromechanical parameters of water. Moreover anthropogenic threats to coral reefs have been specified, including diving tourism, ecological disasters (e.g. oil spills) and the development of marine aquaristics. Rapid changes in the basic living conditions are dangerous for corals and their symbionts and may cause the unsuitability of the new environment resulting in diseases such as coral bleaching. Corals bleaching is a disease associated with the break of the coral and algae relationship which results in a coral reef death on a global scale. Awareness of these negative factors, often related to human activity, may allow us to better understand the ecological processes that are the basis of reef functioning and might enable us to prevent and oppose to the changes and ecological recessions of coral reefs.


Author(s):  
Yume Imada

Abstract Different physical structures play a central role in animal camouflage. However, in evolutionary studies of mimicry, the ecological and evolutionary significance of such structures has been poorly investigated. Larvae of long-bodied craneflies, Cylindrotominae, are all obligate herbivores and resemble plants. They are distinctively characterized by possessing numerous elongated cuticular lobes on the integument. A comprehensive overview of the biology and morphology of cylindrotomids, particularly their larval stages, is laid out, providing original data on nine species. To explore the ecological background of moss resemblance, host-plants of most examined species are clarified, revealing that terrestrial moss-feeding species tend to use specific groups of mosses, either belonging to Bryales or Hypnales. However, the evolution of cryptic forms remains paradoxical, due to the apparent absence of visual predators. Based on histological examinations, extensive internal musculatures within the cuticular lobes on the lateral side are discovered, shedding new light on their function in locomotion. Traditional functional explanations for these lobes, particularly as devices for respiration, locomotion and attachment, are challenged. This study promotes our understanding of the ecomorphology of mimicry devices, which is an angle often dismissed in evolutionary studies of mimicry.


Author(s):  
Marie V. Lebour

The present paper is a continuation of last year's work on the Euphausiidæ in the neighbourhood of Plymouth (Lebour, 1924), in which the early larval stages were described of Nyctiphanes Couchii, Meganyctiphanes norvegica and, less fully, those of Thysanoessa inermis and T. neglecta. These two last-named forms are reserved for a detailed description in another paper, only Nyctiphanes and Meganyctiphanes being dealt with here. The first paper described these as far as the last Calyptopis stages, and it was shown that they were much alike although perfectly distinct, especially as regards colour. The nauplii and metanauplii were easily distinguishable. The whole of the remaining life-history of Nyctiphanes Couchii has now been elucidated and also that of Meganyctiphanes norvegica, with the exception of a few late larval stages. The absence of these, however, does not materially affect our knowledge of its life-history.


Author(s):  
Michael Belitz ◽  
Vijay Barve ◽  
Joshua Doby ◽  
Maggie Hantak ◽  
Elise Larsen ◽  
...  

Insect phenological lability is key for determining which species will adapt under environmental change. However, little is known about when adult insect activity terminates, and overall activity duration. We used community-science and museum specimen data to investigate the effects of climate and urbanization on timing of adult insect activity for 101 species varying in life history traits. We found detritivores and species with aquatic larval stages extend activity periods most rapidly in response to increasing regional temperature. Conversely, species with subterranean larval stages have relatively constant durations regardless of regional temperature. Multivoltine and univoltine species both extended their period of adult activity similarly in warmer conditions. Longer adult durations may represent a general response to warming, but voltinism data in subtropical environments is likely underreported. This effort provides a framework to address drivers of adult insect phenology at continental scales, and a basis for predicting species response to environmental change.


Author(s):  
J. E. Morton

The Plymouth Fauna List contains records of two genera of pteropods, Limacina and Clione. Of the first, Limacina retroversa (Flem.) is by far the better-known species, apparently occurring regularly at Plymouth in large numbers in townettings from outside, and sometimes inside, the Sound. It breeds at Plymouth from June to August, and Lebour (1932) has given a detailed account of its breeding and larval stages and has discussed its role in the plankton. The second species of Limacina at Plymouth is lesueuri (d'Orbigny), which has been observed from time to time since 1906, when it was very common. The last record in the Fauna is off the Breakwater in 1920. Of the gymnosomatous pteropods, Clione limacina Phipps is the only species regularly occurring. Lebour (1931) has described the life history of this form, and mentions February to August as its months of greatest abundance. Its breeding season is June to August. Another gymnosome, tentatively referred to as Clionina longicauda, is reported by Russell (1936), and from the specimen department at Plymouth Laboratory the writer obtained some preserved specimens, not easily identifiable, of a Pneumodermopsis taken locally; its species is perhaps ciliata, recorded by Massy (1917) from the Irish Coast.


2018 ◽  
pp. 403-424
Author(s):  
Matthew R. Walsh ◽  
Michelle Packer ◽  
Shannon Beston ◽  
Collin Funkhouser ◽  
Michael Gillis ◽  
...  

Much research has shown that variation in ecological processes can drive rapid evolutionary changes over periods of years to decades. Such contemporary adaptation sets the stage for evolution to have reciprocal impacts on the properties of populations, communities, and ecosystems, with ongoing interactions between ecological and evolutionary forces. The importance and generality of these eco-evolutionary dynamics are largely unknown. In this chapter, we promote the use of water fleas (Daphnia sp.) as a model organism in the exploration of eco-evolutionary interactions in nature. The many characteristics of Daphnia that make them suitable for laboratory study in conjunction with their well-known ecological importance in lakes, position Daphnia to contribute new and important insights into eco-evolutionary dynamics. We first review the influence of key environmental stressors in Daphnia evolution. We then highlight recent work documenting the pathway from life history evolution to ecology using Daphnia as a model. This review demonstrates that much is known about the influence of ecology on Daphnia life history evolution, while research exploring the genomic basis of adaptation as well as the influence of Daphnia life history traits on ecological processes is beginning to accumulate.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Zorana Kurbalija Novičić ◽  
Ahmed Sayadi ◽  
Mihailo Jelić ◽  
Göran Arnqvist

Abstract Background Understanding the forces that maintain diversity across a range of scales is at the very heart of biology. Frequency-dependent processes are generally recognized as the most central process for the maintenance of ecological diversity. The same is, however, not generally true for genetic diversity. Negative frequency dependent selection, where rare genotypes have an advantage, is often regarded as a relatively weak force in maintaining genetic variation in life history traits because recombination disassociates alleles across many genes. Yet, many regions of the genome show low rates of recombination and genetic variation in such regions (i.e., supergenes) may in theory be upheld by frequency dependent selection. Results We studied what is essentially a ubiquitous life history supergene (i.e., mitochondrial DNA) in the fruit fly Drosophila subobscura, showing sympatric polymorphism with two main mtDNA genotypes co-occurring in populations world-wide. Using an experimental evolution approach involving manipulations of genotype starting frequencies, we show that negative frequency dependent selection indeed acts to maintain genetic variation in this region. Moreover, the strength of selection was affected by food resource conditions. Conclusions Our work provides novel experimental support for the view that balancing selection through negative frequency dependency acts to maintain genetic variation in life history genes. We suggest that the emergence of negative frequency dependent selection on mtDNA is symptomatic of the fundamental link between ecological processes related to resource use and the maintenance of genetic variation.


2018 ◽  
Vol 69 (6) ◽  
pp. 942 ◽  
Author(s):  
Daisuke Goto ◽  
Martin J. Hamel ◽  
Mark A. Pegg ◽  
Jeremy J. Hammen ◽  
Matthew L. Rugg ◽  
...  

Environmental regimes set the timing and location of early life-history events of migratory species with synchronised reproduction. However, modified habitats in human-dominated landscapes may amplify uncertainty in predicting recruitment pulses, impeding efforts to restore habitats invaluable to endemic species. The present study assessed how environmental and spawner influences modulate recruitment variability and persistence of the Missouri River shovelnose sturgeon (Scaphirhynchus platorynchus) under modified seasonal spawning and nursery habitat conditions. Using a spatially explicit individual-based biophysical model, spawning cycle, early life-history processes (dispersal, energetics and survival) and prey production were simulated under incrementally perturbed flow (from –10 to –30%) and temperature (+1 and +2°C) regimes over 50 years. Simulated flow reduction and warming synergistically contracted spring spawning habitats (by up to 51%) and periods (by 19%). Under these conditions, fewer mature females entered a reproductive cycle, and more females skipped spawning, reducing spawning biomass by 20–50%. Many spawners migrated further to avoid increasingly unfavourable habitats, intensifying local density dependence in larval stages and, in turn, increasing size-dependent predation mortality. Diminished egg production (by 20–97%) and weakened recruitment pulses (by 46–95%) ultimately reduced population size by 21–74%. These simulations illustrate that environmentally amplified maternal influences on early life histories can lower sturgeon population stability and resilience to ever-increasing perturbations.


2010 ◽  
Vol 61 (9) ◽  
pp. 999 ◽  
Author(s):  
C. Cvitanovic ◽  
A. S. Hoey

The removal of macroalgae by herbivores is fundamental to the long-term persistence of coral reefs. Variation in macroalgal browsing has been documented across a range of spatial scales on coral reefs; however, few studies have examined the factors that influence within-habitat rates of herbivory. The aim of the present study was to quantify herbivory on two species of Sargassum across three bays on an inshore island in the central Great Barrier Reef (GBR), and to determine whether these removal rates were related to the benthic composition or herbivorous fish communities. Removal rates of Sargassum differed significantly among bays, with removal rates in the southern bay (66.9–83.0% per 3 h) being approximately double that of the two other bays (29.2–38.5% per 3 h). The removal rates displayed a direct relationship with the benthic community structure, in particular the cover of macroalgae and live plate corals. Although it is difficult to determine whether these relationships are related to the availability of food resources or the structural complexity of the substratum, they highlight the potential influence of benthic composition on ecological processes. Quantifying and understanding the drivers of herbivory across a range of spatial scales is essential to the future management of coral reefs.


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