Shore to landward transect burrow diversity of fiddler crab in a tropical intertidal coast of Chittagong in Bangladesh

Burrows indicate the abundance and distribution of fiddler crab in an intertidal coast that varies with structure and morphology within intertidal habitats. We observed fiddler crab burrow density and characters (burrow length, depth, diameter and volume) within randomly selected six 1m2 quadrate from three intertidal habitats: higher saltmarsh, mangrove pool (a small ditch distributed within mangrove) and mangrove land through field surveys in a coast of Chittagong, Bangladesh. Burrows were observed and counted for density estimation, and burrow characteristics were studied through excavating 10 representative burrows from each quadrate of each habitat. Spearman correlation was used to relate between the distances (from shore towards land) and burrow characters. Transect starting from saltmarsh as base towards mangrove land showed burrow density decreased from shore to higher intertidal habitat. Simultaneously, higher burrow length and diameter were observed landward and contrariwise shoreward. Burrow prevalence in mangrove pools represents fiddler crabs are abundant within land and shore interface presumably due to the dual privilege of easy burrowing and moist condition required for gill ventilation.Res. Agric., Livest. Fish.4(2): 131-140, August 2017

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Seasonal variation in the abundance and distribution of Anomalocardia flexuosa (Mollusca, Bivalvia, Veneridae) in an estuarine intertidal plain

PeerJ ◽

10.7717/peerj.4332 ◽

2018 ◽

Vol 6 ◽

pp. e4332 ◽

Cited By ~ 1

Author(s):

Jacqueline S. Silva-Cavalcanti ◽

Monica F. Costa ◽

Luis H.B. Alves

Keyword(s):

Seasonal Variation ◽

Shell Length ◽

River Flow ◽

Northeast Brazil ◽

High Biomass ◽

Important Food ◽

Intertidal Habitats ◽

Density And Biomass ◽

Abundance And Distribution ◽

Recruitment Period

Spatial and temporal density and biomass of the infaunal mollusk Anomalocardia flexuosa (Linnaeus, 1767) evaluated a tidal plain at Goiana estuary (Northeast Brazil). Three hundred and sixty core samples were taken during an annual cycle from three intertidal habitats (A, B and C). Shell ranged from 2.20 to 28.48 mm (15.08 ± 4.08 mm). Recruitment occurred more intensely from January to March. Total (0–1,129 g m−2) differed seasons (rainy and dry), with highest values in the early rainy season (221.0 ± 231.44 g m−2); and lowest values in the late dry season (57.34 ± 97 g m−2). The lowest occurred during the late rainy (319 ± 259 ind m−2) and early dry (496 ± 607 ind m−2) seasons. Extreme environmental situations (e.g., river flow, salinity and water temperature) at the end of each season also affected density ranges (late dry: 0–5,798 ind m−2; late rainy: 0–1,170 ind m−2). A. flexuosa in the Goiana estuary presented a dominance of juvenile individuals (shell length < 20 mm), with high biomass main the recruitment period. Average shell length, density and biomass values suggest overfishing of the stock unit. A. flexuosa is an important food and income resource along its whole distribution range. The species was previously also known as Anomalocardia brasiliana (Gmelin, 1791).

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Intertidal habitats and benthic macrofauna of the Forth estuary, Scotland

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000006837 ◽

1987 ◽

Vol 93 (3-4) ◽

pp. 389-399 ◽

Cited By ~ 5

Author(s):

Donald S. McLusky

Keyword(s):

Benthic Macrofauna ◽

Salinity Range ◽

Intertidal Habitat ◽

Important Food ◽

Lower Estuary ◽

Fine Grained ◽

Important Food Source ◽

Intertidal Habitats ◽

Lower Biomass ◽

Middle Estuary

SynopsisThe intertidal habitats of the Forth estuary are dominated by fine-grained muds, which experience a salinity range of 0–32%, j over the length of the estuary from Stirling to Queensferry. The current total area of the intertidal zone is 23.3 km2, the majority of which is found in the three central bays of Skinflats, Kinneil and Torry Bay. Over the centuries, agricultural and industrial reclamation has reduced by almost 50% the size of the Forth estuary intertidal habitat. The upper estuary has narrow intertidal shores, inhabited almost exclusively by oligochaete worms, which are very abundant due to organic enrichment of the area. The middle estuary is responsible for the greatest biomass and production of the intertidal benthic macrofauna. The lower estuary has a greater diversity of species than the upper and middle estuary, but has a lower biomass and abundance of macrofauna. It is shown that the production/biomass (P/B) ratio of several species in the Forth estuary is lower than that of the same species in other estuaries. This depression cannot be explained by natural environmental variables, and is suggested as being due to the levels of pollutants throughout the area. Despite this depressed productivity, and the threats from further reclamation, the Forth estuary retains abundant populations of intertidal animals, which are an important food source for birds and fish.

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Fiddler Crab Behavioral Ecology: Burrow Density in Uca Pugnax (Smith) and Uca Pugilator (Bosc) (Decapoda Brachyura)

Crustaceana ◽

10.1163/156854078x00790 ◽

1978 ◽

Vol 34 (3) ◽

pp. 235-244 ◽

Cited By ~ 21

Author(s):

Wayne P. Aspey

Keyword(s):

Behavioral Ecology ◽

Fiddler Crab ◽

Uca Pugnax ◽

Uca Pugilator ◽

Burrow Density

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Quantifying Intertidal Habitat Relative Coverage in a Florida Estuary Using UAS Imagery and GEOBIA

Remote Sensing ◽

10.3390/rs12040677 ◽

2020 ◽

Vol 12 (4) ◽

pp. 677

Author(s):

Michael C. Espriella ◽

Vincent Lecours ◽

Peter C. Frederick ◽

Edward V. Camp ◽

Benjamin Wilkinson

Keyword(s):

Salt Marshes ◽

Coastal Development ◽

Surface Model ◽

Oyster Reefs ◽

Intertidal Habitat ◽

Habitat Monitoring ◽

Object Based ◽

Geometric Context ◽

Geographic Object ◽

Intertidal Habitats

Intertidal habitats like oyster reefs and salt marshes provide vital ecosystem services including shoreline erosion control, habitat provision, and water filtration. However, these systems face significant global change as a result of a combination of anthropogenic stressors like coastal development and environmental stressors such as sea-level rise and disease. Traditional intertidal habitat monitoring techniques are cost and time-intensive, thus limiting how frequently resources are mapped in a way that is often insufficient to make informed management decisions. Unoccupied aircraft systems (UASs) have demonstrated the potential to mitigate these costs as they provide a platform to rapidly, safely, and inexpensively collect data in coastal areas. In this study, a UAS was used to survey intertidal habitats along the Gulf of Mexico coastline in Florida, USA. The structure from motion photogrammetry techniques were used to generate an orthomosaic and a digital surface model from the UAS imagery. These products were used in a geographic object-based image analysis (GEOBIA) workflow to classify mudflat, salt marsh, and oyster reef habitats. GEOBIA allows for a more informed classification than traditional techniques by providing textural and geometric context to habitat covers. We developed a ruleset to allow for a repeatable workflow, further decreasing the temporal cost of monitoring. The classification produced an overall accuracy of 79% in classifying habitats in a coastal environment with little spectral and textural separability, indicating that GEOBIA can differentiate intertidal habitats. This method allows for effective monitoring that can inform management and restoration efforts.

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First record and conservation value of Periophthalmus malaccensis Eggert from Borneo, with ecological notes on other mudskippers (Teleostei: Gobiidae) in Brunei

Scientia Bruneiana ◽

10.46537/scibru.v15i0.42 ◽

2016 ◽

Vol 15 ◽

Cited By ~ 2

Author(s):

Gianluca Polgar

Keyword(s):

Population Density ◽

Coastal Wetlands ◽

Conservation Status ◽

First Record ◽

Conservation Value ◽

Habitat Types ◽

Field Surveys ◽

Brunei Darussalam ◽

Historical Times ◽

Intertidal Habitats

The mudskipper Periophthalmus malaccensis is first recorded in Borneo, from two mangrove areas of Brunei Darussalam. The distribution and habitat types where this and other ecologically similar mudskippers (Periophthalmus and Periophthalmodon species) were found in Brunei are also described, from field surveys conducted in Bruneian coastal wetlands from 2013 to 2015. P. malaccensis has a relatively restricted geographic distribution, and probably got extinct in historical times in Singapore. In Brunei, this species occurs at low population density in high intertidal habitats, which are highly impacted by anthropogenic destruction and fragmentation. For these reasons, the conservation status of this species should be evaluated.

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Combining survey and remotely sensed environmental data to estimate the habitat associations, abundance and distribution of breeding thin-billed prions Pachyptila belcheri and Wilson’s storm-petrels Oceanites oceanicus on a South Atlantic tussac island

Polar Biology ◽

10.1007/s00300-021-02842-3 ◽

2021 ◽

Author(s):

Allan W. Stokes ◽

Paulo Catry ◽

Jason Matthiopoulos ◽

Megan Boldenow ◽

T. J. Clark ◽

...

Keyword(s):

Vegetation Index ◽

Conservation Status ◽

Breeding Population ◽

Habitat Associations ◽

Environmental Data ◽

Burrow Density ◽

Pachyptila Belcheri ◽

Normalised Difference Vegetation Index ◽

Abundance And Distribution ◽

Oceanites Oceanicus

AbstractSmall petrels are the most abundant seabirds in the Southern Ocean. However, because they breed in burrows on remote and often densely vegetated islands, their colony sizes and conservation status remain poorly known. To estimate the abundance of these species on Bird Island in the Falkland archipelago, we systematically surveyed their breeding burrow density and occupancy across this near-pristine tussac (Poa flabellata)-covered island. By modelling burrow density as functions of topography and Sentinel 2 satellite-derived Normalised Difference Vegetation Index data, we inferred habitat associations and predicted burrow abundance of the commonest species—Thin-billed Prions (Pachyptila belcheri) and Wilson’s Storm-petrels (Oceanites oceanicus). We estimate that there are 631,000 Thin-billed Prion burrows on the island (95% CI 496,000–904,000 burrows). Assuming that burrow occupancy lies between 12 and 97%, this equates to around 76,000–612,000 breeding pairs, making Bird Island the second or third largest P. belcheri colony in the world, holding approximately 3–27% of the species’ breeding population. We estimate that 8200–9800 (95% CI 5,200–18,300 pairs) pairs of Wilson’s Storm-petrels also breed on the island. Notably, the latter burrowed predominantly under and within tussac pedestals, whereas they are usually assumed to breed in rock cavities. Thin-billed Prions are declining in the Kerguelen archipelago, but their population trends in the Falklands are unknown. Given the wide confidence intervals around our own and other population estimates for these cryptic species, we recommend that their populations should be monitored regularly, at multiple sites.

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