scholarly journals Low Densities of the Ghost Crab Ocypode quadrata Related to Large Scale Human Modification of Sandy Shores

2021 ◽  
Vol 8 ◽  
Author(s):  
Carlos A. M. Barboza ◽  
Gustavo Mattos ◽  
Abílio Soares-Gomes ◽  
Ilana Rosental Zalmon ◽  
Leonardo Lopes Costa
Keyword(s):  
Wave Energy ◽  
Natural Habitat ◽  
Sandy Beaches ◽  
Sea Surface ◽  
Ghost Crab ◽  
Natural Systems ◽  
Sandy Shores ◽  
Use Of Resources ◽  
Ocypode Quadrata ◽  
Human Modification

Sandy beaches are the most common ecosystems of coastal regions and provide direct and indirect essential services for millions of people, such as coastal protection, fishing, tourism, and recreational activities. However, the natural habitats of sandy shores are being modified at rates never experienced before, making beaches key monitoring sites of marine ecosystems worldwide. The ghost crab species Ocypode quadrata is the most conspicuous crustacean of sandy beaches along the Western Atlantic coast and has been successfully used as an indicator of anthropogenic disturbance and environmental variability. To investigate the potential role of a “triple whammy” [(1) urbanization; (2) use of resources; (3) decreasing resilience] on the most common bioindicator of sandy shores, we compiled a dataset including 214 records of burrows density from 94 microtidal sandy beach sectors covering a range of over 65° of latitude. The response of burrows density to synergetic effects of human modification of natural systems and environmental changes was investigated using linear models. We used the cumulative Human Modification (HMc) index, a standardized geographic projection of changes of natural systems, as a predictor of urbanization, industrialization and use of resources. The predictor wave energy, tidal range and temperature (sea surface and air) were included as potential effects of climate changes. Literature review showed records mainly concentrated at sub-tropical and temperate regions. HMc values were clearly negatively related to burrows density, thereby supporting an effect of modification of natural habitat at large spatial scale. Sea surface temperature and air temperature were positive related with density and the lack of a general pattern of the relationship between burrows density, interactions between wave energy and tide range, supported unclear patterns reported at regional scales. Finally, we argue that ghost crabs are valuable targets for protection actions on sandy beaches that can benefit coexisting species and provide natural habitat conservation.

Number of ghost crab burrows does not correspond to population size

2013 ◽  
Vol 8 (9) ◽  
pp. 843-847 ◽  
Author(s):  
Willian Silva ◽  
Tereza Calado
Keyword(s):  
Sex Ratio ◽  
Population Size ◽  
Anthropogenic Impacts ◽  
Sandy Beaches ◽  
Ghost Crab ◽  
Ocypode Quadrata ◽  
Ghost Crabs ◽  
The One ◽  
Number Of Individuals

AbstractGhost crabs are distributed worldwide on sandy beaches, and several studies have associated the number of ghost crab burrows with the levels of anthropogenic impacts on the beaches under study. However, our results show that the use of ghost crab Ocypode quadrata burrows to assess levels of anthropogenic impacts on sand beaches may not be accurate, as previously thought, because the number of burrows does not represent an estimate of the population size. In addition, we propose three hypotheses to explain the extremely low number of individuals/number of burrows ratio: the “secret chamber”, the “multiple openings”, and the “one crab, several burrows” hypotheses. We also observed an unusual sex ratio.

Mortality of the Atlantic ghost crab Ocypode quadrata (Fabricius, 1787) due to vehicle traffic on sandy beaches: A road ecology approach

2020 ◽  
Vol 260 ◽  
pp. 110168 ◽  
Author(s):  
Leonardo Lopes Costa ◽  
Helio Secco ◽  
Vitor Figueira Arueira ◽  
Ilana Rosental Zalmon
Keyword(s):  
Road Ecology ◽  
Sandy Beaches ◽  
Ghost Crab ◽  
Vehicle Traffic ◽  
Ocypode Quadrata

Effect of Iron Limitation on the Ultrastructure of Agmenellum Quadruplicatum

1981 ◽  
Vol 39 ◽  
pp. 410-411
Author(s):  
L. P. Hardie ◽  
D. L. Balkwill ◽  
S. E. Stevens
Keyword(s):  
Growth Medium ◽  
Green Alga ◽  
Natural Habitat ◽  
Iron Limitation ◽  
Natural Environments ◽  
Blue Green Alga ◽  
Marine Cyanobacterium ◽  
Natural Systems ◽  
Thin Sectioning ◽  
Agmenellum Quadruplicatum

Agmenellum quadruplicatum is a unicellular, non-nitrogen-fixing, marine cyanobacterium (blue-green alga). The ultrastructure of this organism, when grown in the laboratory with all necessary nutrients, has been characterized thoroughly. In contrast, little is known of its ultrastructure in the specific nutrient-limiting conditions typical of its natural habitat. Iron is one of the nutrients likely to limit this organism in such natural environments. It is also of great importance metabolically, being required for both photosynthesis and assimilation of nitrate. The purpose of this study was to assess the effects (if any) of iron limitation on the ultrastructure of A. quadruplicatum. It was part of a broader endeavor to elucidate the ultrastructure of cyanobacteria in natural systemsActively growing cells were placed in a growth medium containing 1% of its usual iron. The cultures were then sampled periodically for 10 days and prepared for thin sectioning TEM to assess the effects of iron limitation.

Can the Atlantic ghost crab be a potential biomonitor of microplastic pollution of sandy beaches sediment?

2019 ◽  
Vol 145 ◽  
pp. 5-13 ◽  
Author(s):  
Leonardo Lopes Costa ◽  
Vitor Figueira Arueira ◽  
Mônica Ferreira da Costa ◽  
Ana Paula Madeira Di Beneditto ◽  
Ilana Rosental Zalmon
Keyword(s):  
Sandy Beaches ◽  
Ghost Crab

MODELING SPILLED OIL PARTITIONING IN NEARSHORE AND SURF ZONE AREAS

1985 ◽  
Vol 1985 (1) ◽  
pp. 379-383 ◽  
Author(s):  
Erich R. Gundlach ◽  
Timothy W. Kana ◽  
Paul D. Boehm
Keyword(s):  
Wave Energy ◽  
Surf Zone ◽  
High Energy ◽  
Sandy Beaches ◽  
Coarse Grained ◽  
Tidal Range ◽  
Incoming Wave ◽  
Fine Grained ◽  
Beach Sediments ◽  
Rocky Coasts

ABSTRACT The shoreline of a potential spill impact area can be divided into units, each with a specific geomorphology. As oil enters each unit, it will (to varying extents) evaporate, dissolve, interact with suspended particles and sink, biodegrade, photo-oxidize, be transported to the next unit, or strand on the shoreline. In the last case, oil will reenter the aquatic system after a given time and again be exposed to these same processes. For modeling purposes, the world's shorelines can be divided into sedimentary beaches and tectonic rocky coasts, varying in wave energy and tidal range. The size of beach sediments can range from very coarse grained (gravels) to very fine grained (silts and clays). Coarse-grained shorelines have higher incoming wave energy than fine-grained areas. Along all coasts, several partitioning components remain relatively constant for medium to light crude oils, e.g., evaporation (30 to 50 percent) and biodegradation/photo-oxidation (0 to 5 percent). Others may vary substantially. For instance, sedimentation may reach 10 to 20 percent in fine-grained estuaries, but only 0 to 2 percent along high energy coasts having very coarse-grained bottom sediments. Similarly, along sandy beaches the stranding of oil along the shoreline may reach 25 to 35 percent, as compared to only 1 to 2 percent along steep, rocky coasts. Dissolution, in general, does not vary so radically, being approximately 10 to 15 percent along high-energy rocky coasts, as compared to 5 to 10 percent in sheltered estuaries that do not have the mixing energy to drive additional oil into the water column.

Sign in / Sign up

Export Citation Format

Share Document