Ecology and behaviour of immature Culicoides melleus (Coq.) (Dipt., Ceratopogonidae)

1972 ◽  
Vol 62 (1) ◽  
pp. 113-127 ◽  
Author(s):  
J. R. Linley ◽  
G. M. Adams
Keyword(s):  
Intertidal Zone ◽  
Laboratory Experiments ◽  
High Tide ◽  
Time Of Day ◽  
Fourth Instar ◽  
Tidal Level ◽  
Sand Surface ◽  
Tide Level ◽  
The Vertical Distribution ◽  
Incoming Tide

The distribution of the larvae and pupae of Culicoides melleus (Coq.) in a natural beach habitat in an inlet on the Florida coast was studied in relation to tidal level and time of day. Larvae and pupae were confined to the intertidal zone and these distributions were unaffected by time of day or tidal level. Distributions of younger larval instars were displaced towards the inferred area of oviposition at higher elevations on the beach. Pupae were associated with the zone at and somewhat below high tide level. Differences in the vertical distribution of larvae between 0 and 2 in. deep between dark (pre-dawn)/low tide, morning/low tide and afternoon/low tide conditions were probably associated with larval response to light and heat.In laboratory experiments with a temperature gradient, second- to fourth-instar larvae preferred the 18–25°C range, but the fourth instars were the least discriminating. Laboratory experiments with a simulated beach showed that pupae flooded on an incoming tide remained in their burrows and immediately buried themselves more deeply when waves were generated in the water; they were able to return to the surface if buried, and survived drowning for four days. Inundated areas were avoided as pupation sites. The orientation of pupae at the sand surface and their formation in burrows was related to negative phototactic responses of the pupating larvae.

scholarly journals The vertical distribution of phytal ostracods in the intertidal zone at Gore Point, Bristol Channel, U.K.

1982 ◽  
Vol 1 (1) ◽  
pp. 71-84 ◽  
Author(s):  
David J. Horne
Keyword(s):  
New Species ◽  
Vertical Distribution ◽  
Age Structure ◽  
Intertidal Zone ◽  
Life Cycles ◽  
Individual Species ◽  
Tidal Level ◽  
Percentage Composition ◽  
Annual Water ◽  
The Vertical Distribution

Abstract. The first detailed investigation of the vertical distribution of ostracods inhabiting intertidal algae is presented herein. A study was made of the ostracod faunas obtained from samples of Corallina collected at various levels along transects of the intertidal zone at Gore Point in the Bristol Channel. A total of 28 species were recorded, including four new species presently left in open nomenclature. Both the composition of the ostracod fauna and the population age structure of individual species were found to vary considerably according to tidal level. The development of instars apparently proceeds at a faster rate at higher tidal levels, probably due to higher mean annual water temperatures. Among the factors which may determine the percentage composition of the ostracod fauna at a given level are temperature, pH, and the life-cycles and migratory habits of individual species.

Effects of the Large-Scale Reclamation Project on Hydro-Dynamic Environment in the Estuary

2012 ◽  
Vol 226-228 ◽  
pp. 2317-2322 ◽  
Author(s):  
Jin Bin Mu ◽  
Shi Chang Huang ◽  
Hai Feng Lou
Keyword(s):  
Large Scale ◽  
Flow Model ◽  
High Tide ◽  
Dynamic Environment ◽  
Tidal Level ◽  
Tide Level ◽  
Reclamation Project ◽  
Volume Method ◽  
Shallow Flow Model ◽  
Good Agreement

The hydro-dynamic environment will be changed after reclamation project building. It will affect the navigation, estuary regime, tidal prism, flood controlling, storm surge and so on. Taking the shore reclamation between Oujiang and Feiyunjiang estuary as example, a tidal current mathematical model is used to study the effects of the large-scale reclamation on the hydro-dynamic environment. Based on triangle grid and finite volume method, the shallow flow model is examined by 9 tidal level stations and 9 observed synchronous vertical lines. And the comparison between computed result and measured solution demonstrates very good agreement. After the project building, the high tide level reduces to a certain extent and the flow of front reclamation line reduces by a big margin. But it is a little influence to the core ports of Wenzhou. And the tidal influx through Feiyunjiang Estuary decreases. The result can provide important reference and inspiration for the effects of hydro-dynamic environment due to the large-scale reclamation projects.

An experimental study of the pattern and significance of the climbing behaviour of Hydrobia ulvae

1981 ◽  
Vol 61 (2) ◽  
pp. 285-299 ◽  
Author(s):  
R. S. K. Barnes
Keyword(s):  
Population Density ◽  
Laboratory Experiments ◽  
Field Experiments ◽  
High Tide ◽  
Field Observations ◽  
Laboratory Studies ◽  
Hydrobia Ulvae ◽  
Tidal Water ◽  
Climbing Behaviour ◽  
Incoming Tide

The climbing behaviour of the gastropod Hydrobia ulvae (Pennant) and its relationship with flotation/dispersal were investigated by field observations and experiments in Norfolk, U.K. and by laboratory experiments. Field experiments of the type used by previous authors were discontinued when it was observed that counts at low tide of snails which had climbed objects the previous high tide did not reflect adequately climbing activity during that period of tidal cover. Both field and laboratory studies yielded five general results: (i) snails climbed only when covered by tidal water; (ii) climbing activity was not related to population density; (iii) climbing activity, under conditions of constant population density, varied markedly during the cycle of spring tidal cover, reaching a peak after the first few tides and declining rapidly thereafter; (iv) maximum numbers of snails were present on submerged structures relatively early in any given period of cover and declined (snails crawled downwards off the structure) as the period of cover continued; and (v) rarely were large proportions of climbed Hydrobia floated off their support by the incoming tide; this was associated only with conditions of extreme calm.

Studies on Benthos in the Intertidal Zone of Sanddy Mud Flats at Sanmen Bay, the East China Sea

2012 ◽  
Vol 518-523 ◽  
pp. 5138-5142 ◽  
Author(s):  
Chen Jing Jiang ◽  
Gen Hai Zhu ◽  
Qing Song Zhou ◽  
Jian Qian
Keyword(s):  
Community Structure ◽  
Vertical Distribution ◽  
Intertidal Zone ◽  
High Tide ◽  
The East China Sea ◽  
Predominant Species ◽  
Sanmen Bay ◽  
Cerithidea Cingulata ◽  
Species Composition And Distribution ◽  
The Vertical Distribution

This paper first reported species composition and distribution of biomass, habitat density and characteristics of community structure of benthos. The result has showed that 64 species is first recorded from intertidal zone at Sanmen, of which, most are eurythermal and eurychoric species, and the predominant species are Bluecoat exert, Morale iridescent,Cerithidea cingulata, Lunatia gilva, Laternula marilina and Gaetice depressus etc. .The range of benthic biomass is from 234.25g/m2 to 440g/m2; and habitat density is from 955.0 ind./m2 to 2950.0 ind./m2. The vertical distribution has shown that species, biomass and habitat density sequence on the intertidal zone are middle tide region > low tide region > high tide region.

NODAL CYCLE, QUASI-LUNAR CYCLE, AND FLORIDA CURRENT INFLUENCES ON HIGH TIDE LEVEL IN MIAMI FLORIDA

2020 ◽  
Author(s):  
Martina Rogers ◽  
◽  
Michael C. Sukop ◽  
Jayantha Obeysekera ◽  
Florence George ◽  
...  
Keyword(s):  
High Tide ◽  
Lunar Cycle ◽  
Florida Current ◽  
Tide Level

scholarly journals Filamentous fungi isolated from sand and water of "Bairro Novo" and "Casa Caiada" beaches, Olinda, Pernambuco, Brazil

2008 ◽  
Vol 68 (3) ◽  
pp. 577-582 ◽  
Author(s):  
DNF. Gomes ◽  
MAQ. Cavalcanti ◽  
MJS. Fernandes ◽  
DMM. Lima ◽  
JZO. Passavante
Keyword(s):  
Water Samples ◽  
Water Surface ◽  
High Tide ◽  
Sand Sample ◽  
Distilled Water ◽  
Sabouraud Agar ◽  
Sand Surface ◽  
Heterotrophic Microorganisms ◽  
Petri Dishes ◽  
Dry And Rainy Seasons

Fungi comprehend a heterogeneous group of heterotrophic microorganisms that act as saprobes or parasites or, less frequently, as symbionts living in association with other organisms. They are cosmopolitan and important components of ecosystems. Considering the small number of Brazilian papers on the filamentous mycota in marine environments, and the need to improve knowledge of the diversity of these microfungi in "Casa Caiada" and "Bairro Novo" beaches, Olinda, PE, the aim of this work was to isolate and identify the fungi from sand and water samples of these ecosystems. Thirty two samplings of sand (surface and 20 cm deep) and water (surface and 1 m deep) were carried out during the dry and rainy seasons, in low and high tide. From each sand sample, a suspension was made with 50 g of sand diluted in 90 mL of sterilized distilled water. From each sand suspension and water sample, 0.5 mL was spread, in triplicate, onto Petri dishes containing Sabouraud Agar added of chloramphenicol. The plates were incubated at 28 °C (±2 °C). Fifty seven species were isolated, identified, and classified in 20 genera. Aspergillus and Penicillium were the most frequent genera in both sand and water, with a total of 11 and 19 species, respectively.

scholarly journals Intertidal habitat use of bottlenose dolphins (Tursiops truncatus) in Bahía San Antonio, Argentina

2017 ◽  
Vol 98 (5) ◽  
pp. 1109-1118
Author(s):  
Els Vermeulen
Keyword(s):  
Habitat Use ◽  
Intertidal Zone ◽  
Tursiops Truncatus ◽  
San Antonio ◽  
Bottlenose Dolphins ◽  
High Tide ◽  
Marine Conservation ◽  
Shallow Waters ◽  
Encounter Rate ◽  
Western Atlantic

Very little information is available on bottlenose dolphin (Tursiops truncatus) habitat use in the South-western Atlantic. It is, however, essential in understanding their ecology and to improve conservation management. In this study, habitat use of bottlenose dolphins was examined in Bahía San Antonio, an area frequented by the species. Given the large tidal amplitude and extended intertidal zone in this bay, special focus was given to the intertidal vs subtidal habitat use patterns. Bottlenose dolphins were observed in only half of the surveyed area, with on average 1 dolphin group encountered per 100 km surveyed. All dolphin groups were seen in shallow waters <10 m deep. GLM analyses showed that especially during high tide, depth had an important effect on the dolphin encounter rate, with most dolphin groups encountered in the intertidal zone. While in the intertidal zone, most dolphin groups were observed to be engaged in surface feeding activities. The presented data indicate dolphins remained in shallow waters, and moved to the intertidal zone during high tide where they appear to find feeding opportunities. This information is believed to be of high value in understanding this population's ecological needs, and essential when aiming to improve marine conservation efforts at times of increased anthropogenic pressures in the area.

scholarly journals VERTICAL VARIATION OP UNDERTOW IN THE SURF ZONE

1988 ◽  
Vol 1 (21) ◽  
pp. 33 ◽  
Author(s):  
Akio Okayasu ◽  
Tomoya Shibayama ◽  
Kiyoshi Horikawa
Keyword(s):  
Laboratory Experiments ◽  
Eddy Viscosity ◽  
Surf Zone ◽  
Viscosity Coefficient ◽  
Laser Doppler Velocimeter ◽  
Vertical Variation ◽  
Two Component ◽  
The Mean ◽  
Eddy Viscosity Coefficient ◽  
The Vertical Distribution

In order to establish a model of the vertical distribution of the undertow, laboratory experiments were performed on uniform slopes of 1/20 and 1/30. The turbulent velocity in the surf zone including the area close to the bottom was measured by using a two-component laser doppler velocimeter. The distributions of the mean Reynolds stress and the mean eddy viscosity coefficient were calculated. Based on the experimental results, a model to predict the vertical profile of the undertow was presented.

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