Retention of herring Clupea harengus larvae inside Minas Basin, inner Bay of Fundy

1993 ◽  
Vol 71 (1) ◽  
pp. 56-63 ◽  
Author(s):  
Rodney G. Bradford ◽  
T. Derrick Iles
Keyword(s):  
Residence Time ◽  
Larval Stage ◽  
Growth Rates ◽  
Yolk Sac ◽  
Clupea Harengus ◽  
Bay Of Fundy ◽  
Absolute Size ◽  
The World ◽  
Length Range ◽  
Species Specific

Minas Basin is one of the most tidally active and rapidly flushed macrotidal embayments in the world. But despite this, ichthyoplankton surveys in 1983 and 1984 have shown that herring larvae from spring spawnings inside the basin are retained and metamorphose there about 4 months after hatching. Both yolk-sac and post-yolk-sac larvae with a length range of about 5–20 mm are found in association at individual stations. Published growth rates suggest a residence time for the large larvae of 50–100 days, which agrees with the known lapsed time between first spawning and the time of the surveys of 60 days. The time for 1% retention of passive contaminants, estimated from known physical oceanographic characteristics, is 5 days. Distributions of smelt larvae and herring larvae within the basin are mutually discrete, which confirms the phenomenon of retention and demonstrates that the maintenance of position is effected by mechanisms that are stock and species specific. The estimated absolute size of the Minas Basin herring stock is at the lower end of the scale for herring stocks generally, and is associated with a correspondingly small retention area. This supports the view that absolute size is determined to a large extent by the area occupied by the larval stage.

Species-specific residence times in the aft part of a pelagic survey trawl: implications for inference of pre-capture spatial distribution using the Deep Vision system

2018 ◽  
Vol 75 (4) ◽  
pp. 1393-1404 ◽  
Author(s):  
Melanie J Underwood ◽  
Shale Rosen ◽  
Arill Engås ◽  
Terje Jørgensen ◽  
Anders Fernö
Keyword(s):  
Spatial Distribution ◽  
Residence Time ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Vision System ◽  
Ground Truth ◽  
Clupea Harengus ◽  
Melanogrammus Aeglefinus ◽  
Camera System ◽  
Species Specific

Abstract In-trawl camera systems promise to improve the resolution of trawl sampling used to ground-truth the interpretation of acoustic survey data. In this study, the residence time of fish in front of the Deep Vision camera system, used to identify, measure and count fish inside the trawl, was analysed to determine the reliability of spatial distribution recorded by the system. Although Atlantic herring (Clupea harengus), haddock (Melanogrammus aeglefinus), and most Atlantic cod (Gadus morhua) moved quickly back through the aft part of the pelagic trawl, saithe (Pollachius virens) spent up to 4 min in front of the system. The residence time increased for saithe and cod when other individuals were present, and cod swimming in the low water flow close to the trawl netting spent longer there than cod at the centre of the trawl. Surprisingly, residence time was not related to the size of the fish, which may be explained by the collective behaviour of shoaling fish. Our findings suggest that while in-trawl images can be used to identify, measure and count most species, when sampling fast-swimming species such as saithe the position inferred from when they were imaged may not reflect the actual spatial distribution prior to capture.

Semiochemical tracks of predaceous Coccinellidae (Coleoptera) modulate feeding attributes and assimilation of nutrients in Zygogramma bicolorata (Coleoptera: Chrysomelidae)

2020 ◽  
Vol 152 (3) ◽  
pp. 330-341
Author(s):  
Priya Patel ◽  
Bhupendra Kumar ◽  
Rekha Upadhyay ◽  
Daya Ram Bhusal ◽  
Dinesh Kumar
Keyword(s):  
Biological Control ◽  
Growth Rates ◽  
The Other ◽  
Zygogramma Bicolorata ◽  
Reduced Body ◽  
The World ◽  
Consumption Rates ◽  
Developmental Rates ◽  
Species Specific ◽  
Conversion Efficiencies

AbstractParthenium hysterophorus Linnaeus (Asteraceae) is a toxic weed found abundantly in major agroecosystems of the world. The weed is inhabited by both phytophagous Chrysomelidae (Coleoptera), used as biocontrol agents, and the predaceous Coccinellidae (Coleoptera). The present investigation was designed to assess the feeding attributes and larval development of Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) in the presence of semiochemical tracks of coccinellid beetles. Results revealed that the presence of coccinellid semiochemical tracks on the weed reduced larval consumption rates, conversion efficiencies, and growth rates. The feeding deterrent effects of the semiochemical tracks were species specific. Larvae accumulated lower concentrations of glucose, proteins, and triacylglycerols and exhibited reduced body biomass in the presence of semiochemical tracks. The coccinellid semiochemical tracks also promoted Z. bicolorata larvae to accelerate their developmental rates and develop faster than the larvae reared in the absence of semiochemical tracks. While the fourth instars consumed food maximally and were heavier, their food use efficiencies were lower than the other instars. Our findings, therefore, suggest that the presence of semiochemical tracks of coccinellids on P. hysterophorus impedes its biological control by Z. bicolorata larvae.

Mathematical modeling of fluid movement inside the eyeball during intravitreal injection

2021 ◽  
pp. 106-109
Author(s):  
D.V. Lipatov ◽  
◽  
S.A. Skladchikov ◽  
N.P. Savenkova ◽  
V.V. Novoderezkin ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Residence Time ◽  
Complex Structure ◽  
Posterior Vitreous Detachment ◽  
Vitreous Body ◽  
Complete Removal ◽  
Intravitreal Injections ◽  
The World

Background. The avalanche-like growth of intravitreal injections in the world has significantly increased interest in the hemodynamics of the processes that occur in the eye when a drug is injected into the vitreous cavity. Every year, the number of intravitreally used drugs and promising areas in which they can be used is growing. This also applies to the creation of new combined medicines and the development of drugs with a long-term therapeutic effect. Aims. Create mathematical model of eyeball to evaluate the movement of the drug substance in it; to estimate the time of the drug's presence in the eye cavity before its complete removal, to characterize the ways of its removal from the eye cavity; to assess the significance of posterior vitreous detachment during the time when the drug is present in the eye cavity; to evaluate the effect on the hydrodynamics of the depth of drug administration. Results. When the drug is administered closer to the center of the eyeball, its residence time increases in comparison with the parietal administration. With a complete posterior detachment of the vitreous body, the time of finding the drug in the eye is prolonged compared to its absence. The obtained results of mathematical modeling of the movement of the drug administered intravitreally cannot be mechanically transferred to the human eye, due to the more complex structure of the latter. Key words: intravitreal injections, vitreous body, mathematic computing.

Thinking honeyeater: nectar maps for the Northern Territory, Australia

2000 ◽  
Vol 6 (1) ◽  
pp. 61 ◽  
Author(s):  
John C. Z. Woinarski ◽  
Greg Connors ◽  
Don C. Franklin
Keyword(s):  
Northern Territory ◽  
Dry Season ◽  
Spatial And Temporal Variation ◽  
Wet Season ◽  
Nectar Production ◽  
The World ◽  
Eucalypt Forests ◽  
The Times ◽  
Species Specific ◽  
Nectar Availability

We create monthly maps of nectar availability for the 1.4 x 106 km2 jurisdiction of the Northern Territory, Australia. These are based on a combination of vegetation mapping and a series of indices of plant species specific nectar scoring. The maps reveal complex spatial and temporal variation in nectar availability, but most notably a greater nectar resource in the monsoon-influenced north than in the arid south, and a peak in nectar availability in the dry season. The latter is associated with the extensive tropical eucalypt forests (especially those co-dominated by Eucalyptus miniata and E. tetrodonta). In contrast, wet season nectar availability in these forests is limited, but riparian and swampland forests, typically dominated by Melaleuca species, provide rich but spatially restricted nectar resources. The extensive and rich nectar resources available in eucalypt forests in the dry season supplement the diets of many species which are not primarily nectarivorous. This resource helps shape the singularity of northern Australian eucalypt forests relative to other extensive forests elsewhere in the world. Nectarivores remain in the system through a combination of movements across a number of scales, habitat shifting, and diet shifting. The latter is aided by the peaking of invertebrate and fruit resources at the times of minimum nectar production; a shuffling in resource availability brought about by the extreme climatic seasonality.

scholarly journals Spatio-temporal patterns of the oceanic conditions and nearshore marine community in the Mid-Atlantic Bight (New Jersey, USA)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7927 ◽  
Author(s):  
Juan C. Levesque
Keyword(s):  
New Jersey ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Environmental Conditions ◽  
Clupea Harengus ◽  
Sediment Type ◽  
Temperature Preference ◽  
Marine Fauna ◽  
The World ◽  
Marine Community

Oceanic environmental conditions influence, shape, and control the geographical range, spatial distribution, abundance, and size composition of marine fauna. Water temperature, salinity, dissolved oxygen, depth, and sediment type influence select fish life-history characteristics and community structure. Marine communities are vulnerable to major changes in environmental conditions, but the response and severity depends on various biological or ecological factors, such as resilience to stress or adaptation. Researchers around the world have predicted and documented numerous alterations in fish communities caused by ongoing significant physicochemical shifts associated with natural and potentially unnatural sources, but published studies describing the historical conditions are lacking for most regions around the world, including the coastal waters off New Jersey. Given the need to understand these processes, a multifaceted investigation was undertaken to describe, evaluate, and compare the oceanic conditions and nearshore marine fauna community off New Jersey during 1988 through 2015. Findings showed the oceanic conditions varied over time and space. Mean surface water temperature increased significantly about 0.6 °C per decade, mean salinity decreased about 1.3 psu per decade, and dissolved oxygen increased 0.09 mg/l per decade. Over 20.4 million fish and invertebrates (1,338.3 mt) representing 214 (water temperature preference classified) species (not including unidentified species) were collected within 15 strata (areas: 12−26) off the coast of New Jersey from 1988 to 2015. Three marine fauna water temperature preference groups (coldwater-adapted, warmwater-adapted, and subtropic-adapted) were identified in the study area. The main coldwater-adapted species collected were longfin squid (Loligo pealei) (n = 2, 225, 975), Atlantic herring (Clupea harengus) (n = 544, 032), and little skate (Leucoraja erinacea) (n = 316, 356), while Atlantic butterfish (Peprilus triacanthus) (n = 2, 873, 138), scup (Stenotomus chrysops) (n = 1, 318, 569), and northern searobin (Prionotus carolinus) (n = 503, 230) represented the warmwater-adapted group. Bay anchovy (Anchoa mitchilli) (n = 9, 227, 960), striped anchovy (Anchoa hepsetus) (n = 245, 214), and Atlantic moonfish (Vomer setapinnis) (n = 38, 691) denoted the subtropic-adapted group. Subtropic-adapted species were the most abundant and coldwater-adapted were the least abundant water temperature preference group. The estimated abundance of coldwater-adapted species declined, warmwater-adapted species slightly increased, and subtropic-adapted species decreased with time, which suggest the environmental conditions are influencing and thereby shifting the marine community.

scholarly journals Chironomidae: Biology, Ecology and Systematics

2021 ◽  
Author(s):  
Zerguine Karima
Keyword(s):  
Life Cycle ◽  
Larval Stage ◽  
Adult Stage ◽  
Aquatic Environments ◽  
Biting Midges ◽  
Important Family ◽  
Theoretical Synthesis ◽  
The Family ◽  
The World ◽  
Holarctic Region

The family of Chironomidae is a group of Diptera insects belonging to the suborder of Nematocera, commonly called “non-biting midges” in the adult stage and “bloodworms” in the larval stage. The Chironomidae are often the most abundant group of macroinvertebrates, in number of species and individuals, encountered in all aquatic environments of freshwater, brackish, terrestrial and even the sea. Likewise, Chironomidae occur in all the continents. The Chironomidae family is divided into 11 sub-families that have diffrent ecological statues. Despite the wealth of data on Chironomidae in the Holarctic region, other parts of the world are poorly studied and few guides to identifying Chironomidae have been produced. This chapter includes a theoretical synthesis on the Chironomidae, it deals with the Biology (life cycle and description of different stages), description of all subfamilies and the ecology of this important family of Diptera.

scholarly journals Species-Specific Knowledge About the Environment: A Biophilosophical View

1969 ◽  
Vol 1 (1) ◽  
Author(s):  
Alfredo Pereira Junior
Keyword(s):  
Animal Species ◽  
Specific Knowledge ◽  
Animal Brain ◽  
The World ◽  
Von Uexküll ◽  
Species Specific

The biological work of Jacob von Uexkull (1934) raised an hypothesis that different animal species living in the same environment would have different knowledge about it. He suggested that each species perceives the world according to the structure of their effectors. In this essay I discuss mechanisms in the animal brain possibly responsible for the "embodied" or "pragmatic" character of cognition.

scholarly journals Classification of integration associations according to the degree of development of a single transport space

2019 ◽  
Vol 27 (2) ◽  
pp. 375-385
Author(s):  
Mikhail S Komov
Keyword(s):  
Economic Growth ◽  
Economic Development ◽  
Growth Rates ◽  
World Economy ◽  
Transport Sector ◽  
Special Importance ◽  
The World ◽  
Definition Of ◽  
Negative Growth

In modern conditions of development of integration processes in the world economy, special importance is attached to the transport sector. The formation of a single transport space (STS) in the regions creates additional opportunities for the economic development of the integrating countries. At the same time, the literature does not pay enough attention to the definition of the essence of the single transport space and the classification of integration associations according to the degree of its development. Therefore, there is a need to develop such a classification. The article substantiates the expediency of classification of integration associations according to the degree of development of a single transport space. The author's formal-logical classification is developed, which is based on three basic types of a single transport space: transport and logistics type provide a positive multiplier of integrated economic growth for all participating countries; innovative-logistic and customs-logistic types cause polarization in the action of the multiplier of integrated economic growth (in particular, both positive and negative growth rates of GDP values of the participating countries are possible); industrial and logistics type provide a zero multiplier of integrated economic growth for all participating countries. The conclusion is made about the possibility of unification and harmonization of transport space in the practice of integration associations on the basis of the developed classification.

scholarly journals Principles of constructed wetlands designing

2019 ◽  
Vol 27 (4) ◽  
pp. 255-263
Author(s):  
Kseniia Y. Rybka ◽  
Nataliia M. Shchegolkova
Keyword(s):  
Constructed Wetlands ◽  
Residence Time ◽  
Aquatic Plants ◽  
Subsurface Water ◽  
Technological Parameters ◽  
Agricultural Wastewater ◽  
Universal Principles ◽  
The World ◽  
Individual Type

Constructed wetlands (CW) - shallow surfaces or subsurface water bodies, planted with higher aquatic plants and designed to treat wastewater - have been actively used in world practice for the last decades. There are no universal principles for designing such systems, so for each combination of landscape (in which a CW is located) and the quality of wastewater, an individual type of CW is selected. The article provides an overview of the principles adopted in the world for calculating the main technological parameters of CWs (choice of the type of CW, calculation of the area of CW, the residence time of the water in the system, the choice of filtering medium, etc.) developed on the basis of numerous functioning objects. The recommendations given in the article are applicable for small and mediumsized CWs intended for the treatment of domestic, storm and agricultural wastewater.

Bactrocera tryoni (Queensland fruit fly).

2021 ◽  
Author(s):  
Alan Meats
Keyword(s):  
Host Range ◽  
Larval Stage ◽  
Fruit Fly ◽  
Bactrocera Tryoni ◽  
The World ◽  
Horticultural Pest

Abstract B. tryoni, the Queensland fruit fly, is the most costly horticultural pest in Australia and has invaded several countries in the surrounding region (White and Elson-Harris, 1994). It has the potential to spread to many places around the world because of its wide climatic and host range (Meats 1989b; Sutherst et al., 2000) and a tendency to be carried by human travellers at the larval stage inside infested fruit. B. tryoni is a very serious pest of a wide variety of fruits throughout its range. Damage levels can be anything up to 100% of unprotected fruit.

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