DOCSLIB.ORG

The Mechanism of Rapid Running in the Ghost Crab, Ocypode Ceratophthalma

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Mechanism of Rapid Running in the Ghost Crab, Ocypode Ceratophthalma J. Exp. Biol. (1973), 58, 327-349 327 With 1 plate and 19 text-figures Printed m Great Britain THE MECHANISM OF RAPID RUNNING IN THE GHOST CRAB, OCYPODE CERATOPHTHALMA BY MALCOLM BURROWS* AND GRAHAM HOYLE Department of Biology, University of Oregon, Eugene, Oregon, U.S.A., and Hawaiian Institute of Marine Biology, Coconut Island, Hawaii {Received 19 July 1972) INTRODUCTION Of all crustaceans which move on land, crabs of the genus Ocypode living on tropical sandy beaches achieve the highest speeds. Their rapid, sideways running represents an escape response terminating in the surf or a burrow previously built at or above high-tide mark. When retreat into either of these safe havens is prevented the crab flees at great speed for a short distance but then either prostrates itself in any available depression on the beach or begins to dig itself a new burrow (Cott, 1929). It has been stated that they run sideways using three pairs of walking legs (Koepcke & Koepcke, 1953) or sometimes only two pairs (Gravier, 1922). The impression of high speed is enhanced by supreme agility; they can accelerate rapidly from a standing start, reverse direction abruptly without great loss of speed and rotate their body through 1800 while continuing to run in the same direction (Koepcke & Koepcke, 1953). Estimates of the speed of running have been made many times. Cott (1929) estimated that the O. ceratophtkalma which he observed ' could hardly have been travelling at less than iom.p.h.' (4-4m/sec), while Koepcke & Koepcke (1953) estimated the O.gaudichaudU ran at i-6 m/sec. Hafemann & Hubbard (1969) deter- mined the speed of O. ceratophihalma over unspecified distances on sandy beaches and found an average speed of i-8 m/sec. On the harder surface of a wooden ship's deck the same authors found the average speed increased to 2-3 m/sec, with one individual recorded at 4 m/sec. They found that speed is correlated with body size, measured as width of the carapace, up to a particular size beyond which all the larger crabs ran at approximately the same speed. Hafemann and Hubbard attempted to explain the high speed of running in terms of three specializations of the body. First, the length of the legs for a given body size is greater than for other species of crab from the same habitat; for example Sesarma (Cott, 1929) or Pachygrapsus (Hafemann & Hubbard, 1969). This would allow the length of a step and hence the 'gearing' of the movement to be increased. Secondly, the extensor muscle in the meropodite is always larger than its antagonist, while the reverse is true in other crabs such as Pachygrapsus. This leads to the main power for running being developed about the mero-carpopodite joint in the form of a pushing thrust. Thirdly, since they found the muscles of the leg to have high tetanus fusion-frequencies, of the order of 90 Hz, this might allow the muscles to produce • Present address: Beit Memorial Fellow, Department of Zoology, University of Oxford. 328 M. BURROWS AND G. HOYLE a high rate of cycling of leg movement. Hafemann & Hubbard (1969) calculated that stepping at 90-100 Hz would be necessary to explain the maximum speeds they observed. We were attracted to the problem principally because we were searching for examples of experimentally analyzable central nervous motor programs. The high predicted stepping rates for Ocypode would require complete stepping cycles of only about 10 msec, leaving insufficient time for peripheral sensory feedback to adjust motor output. In addition, since the length changes are relatively large, whilst force requirements are high, specializations of the muscle fibres, a matter in which we are also interested, might have been expected to have occurred. We first tested the ability of the muscles to produce unfused contractions of sufficient magnitude at the high rates required. Although the tetanus fusion-frequency is high, the muscles give very little tension variation at frequencies above 30 Hz, and we estimated that the maximum usable rate would be 25 Hz. This is well below the rate which Hafemann and Hubbard stated would be required and forced us to examine the various aspects of running. We also decided to study the actual rates of movement by electromyography from the running crab. Our findings were some- what surprising, but they do allow us to offer an explanation of rapid running in terms of rates of stepping compatible with the contractile properties of the muscles. They also show a large disparity between the action of the legs on the leading side of the body compared with the trailing side. A difference, though much less than the differences we shall describe below, has recently been shown for Carcinus (Clarac & Coulmance, 1971). MATERIALS AND METHODS Ocypode ceratophthcdma were collected from beaches on the windward side of the island of Oahu, Hawaii. Crabs above 20 mm in carapace width were obtained in the late evening after sunset for they were not visible during the day. By contrast, smaller crabs were common during the daytime. They were kept in a tank with a sloping floor which allowed access to exposed sand or circulating sea water and thus simulated a sloping beach. Most runs were carried out with crabs which had been held captive for less than 24 h. To examine the neuromuscular physiology of leg muscles a third leg was removed, and the muscles were exposed and bathed either in a Ringer's solution containing, in imi/1: Na+, 466; K+, 8; Ca5*, 20; Mg5*, 2; C\~, 502; HCO3-, 8; buffered to pH 70 or in filtered sea water, both at 24-26 °C. Electrical responses of the muscle fibres were recorded with conventional intra- cellular electrodes, and the nerve fibres were stimulated with electrical shocks of variable duration and intensity through a pair of chlorided silver hook electrodes. Tension of the whole muscle was measured by grasping the muscle apodeme between forceps attached to a Grass FTO 3 mechano-electronic transducer. The speed of running was measured using a race track 3 m long by 0-2 m wide having a base of moist, hard-packed sand 40 mm deep. The middle metre of the track was marked by photocells 10 mm wide on to which were focused beams of light. The resolution of the photocells was such that interception of the light beam by the individual legs of a crab as they passed could be detected. Rapid running in ghost crabs 329 The output of the photocells was displayed on a pen recorder which allowed measurement of the time taken to cover 1 m to be made with an accuracy of ± 4 msec. Speed could thus be determined to within at least + 0-5 % over a range 0-5-2-5 m/sec after a start (to permit acceleration) of at least 1 m. Crabs were induced to run in either direction along the track with either the left or right set of legs leading. Those with carapace widths below 12 mm were run on a second, smaller track 600 mm long and 10 mm wide but with the same base of hard-packed sand. The middle 200 mm of this track was monitored by photocells. The gait of the crabs was investigated by first allowing them to run over smooth, moist but firm sand in which the tips of the dactyls left an impression. A clearer picture was obtained by dipping the tips of selected dactyls into acrylic paint of different colours and allowing the crab to run over white paper placed in the 3 m race track. Electromyograms from freely moving crabs were made by inserting 50 fim silver or copper wire insulated but for the tip into the appropriate muscle. The leads were sealed in place using Eastman 910 adhesive and wax of low melting point. The leads were taken to a central anchoring point on the carapace formed by a bracelet of 200 fim copper wire which passed around the body and between the bases of the first and second pairs of legs. From this point the wires ran to a junction box 1 m above the track and then via shielded cables to a.c.-coupled pre-amplifiers with a band width of 80 Hz to 5 kHz. The output of these amplifiers was recorded on an Ampex d.c. tape-recorder for later display on a pen recorder or oscilloscope. The crabs were allowed to move freely across either a circular tank with a diameter of 1 m or along the 3 m track. All behavioural and electromyographic experiments were conducted at ambient air temperatures of 28-32 °C. RESULTS Neuromuscular physiology We measured twitch time, tetanus fusion-frequency, time to peak tetanic contraction and the relaxation time from this for the opener and closer of the dactylopodite, the extensor and flexor of the carpopodite and the levator and depressor of the basipodite. Only the extensor and flexor of the carpopodite will be described in detail (summarized in Table 1) since the others were closely similar. We did not detect any properties which we consider would radically affect the speed of locomotion. Of the two muscles in the meropodite the extensor is heavier by some 30% (Hafemann & Hubbard, 1969). Its fibres arise from a centrally placed apodeme and insert predominantly on the posterior wall of the meropodite, the majority being towards the proximal end of the segment. The colour of the fibres varies along the length of the muscle, there being a central portion of white, translucent fibres bounded proximally and dorsally by a small group of pinkish-brown fibres and distally by a larger group of pink fibres.
Load more

Recommended publications
  • Atti Società Toscana Scienze Naturali
    ATTI DELLA SOCIETÀ TOSCANA DI SCIENZE NATURALI MEMORIE • SERIE B • VOLUME CXXVI • ANNO 2019 Edizioni ETS Serie_b_126/2019BN.indb 1 10/03/20 08:11 Serie_b_126/2019BN.indb 2 10/03/20 08:11 INDICE - CONTENTS S. PASTA, A. TROÌA – From common and used to rare S. MAcciONI, R. VANGELisTI, L. AMADEI – I manoscritti and forgotten: Past and present distribution of the ar- del Museo Botanico pisano. Il “Fondo Gaetano Savi” chaeophyte Euphorbia lathyris L. (Euphorbiaceae) in (1769-1844). southern Italy and Sicily. The manuscripts of Botanic Museum of Pisa. The Col- Da comune e utilizzata a rara e dimenticata: distribuzio- lection of Gaetano Savi (1769-1844). » 61 ne passata e presente dell’archeofita Euphorbia lathyris L. (Euphorbiaceae) in Italia meridionale e Sicilia. pag. 5 G. INNOCENTI, R. MANZONI – Catalogues of the Natural History Museum, Zoological Section “La C.M. MUSARELLA, I. PAGLIANITI, A. CANO-ORTIZ, Specola”, of the University of Florence. XXXIV. G. SPAmpiNATO – Indagine etnobotanica nel territo- Crustacea, Class Malacostraca, Order Decapoda. rio del Poro e delle Preserre Calabresi (Vibo Valentia, Superfamily Portunoidea (Families Geryonidae, S-Italia). Portunidae). Ethnobotanical study in the Poro and Preserre Calabresi Cataloghi del Museo di Storia Naturale dell’Università territory (Vibo Valentia, S-Italy). » 13 di Firenze, Sezione di Zoologia “La Specola”. XXXIV. Crustacea, Classe Malacostraca, Ordine Decapoda. Su- A. DI CENciO, S. CASATI, A. COLLARETA – A new re- perfamiglia Portunoidea (Famiglie Geryonidae, Portu- cord of Ocypode italica (Brachyura: Ocypodidae) from nidae). » 69 the Pliocene of Tuscany (central Italy). Un nuovo esemplare di Ocypode italica (Brachyura: F. CIANFERONI, G. MAZZA, G. INNOCENTI – Presenza Ocypodidae) dal Pliocene della Toscana (Italia centrale).
    [Show full text]
  • Ghost Crab (Ocypode Quadrata) Abundance and Depredation on Loggerhead
    Ghost crab (Ocypode quadrata) abundance and depredation on Loggerhead sea turtle (Caretta caretta) hatchlings on Onslow Beach, North Carolina Sara R. Marschhauser 2010 Advisor: Dr. Christopher DePerno College of Natural Resources, North Carolina State University Advisory Committee: Dr. Stephen Fegley (Institute of Marine Sciences, University of North Carolina) and Dr. Ted Simons (College of Agriculture and Life Sciences, North Carolina State University) Introduction Sea turtles must overcome nest mortality and avoidance of predators following emergence from the nest (Fowler 1979, Miller 2003). Nest mortality can occur due to nest placement, erosion, development of beaches, temperature, and predators (Lutz & Musick 1997, McFarlane 1963). In some locations predators, (e.g., raccoons, foxes and crabs) are the main cause of nest mortality (Barton & Roth 2008, Engeman et al. 2003, Fowler 1979, Garmenstani 2005, Ratnaswany & Warren 1998) and may be the main cause of sea turtle hatchling mortality. Management of sea turtle nests has decreased the mortality of sea turtle nests and hatchlings by some predators in North Carolina (Cordes & Rikard 2005); however, the effect of the current predator management policy of removing raccoons is unknown, but this practice may be causing an increase in other predator populations, such as ghost crabs (Ocypode quadrata). Little is known regarding the depredation rates of sea turtle hatchlings by ghost crabs; however, the abundance and distribution of ghost crabs along Onslow Beach varies dramatically between different areas of the beach (S. Fegley, pers. comm.), which may make sea turtle hatchlings at certain areas of the beach more susceptible to predation. Also, beach characteristics may be responsible for increased depredation.
    [Show full text]
  • Occurrence of Ocypode Cursor (Linnaeus, 1758) (Crustacea, Decapoda) in Salento (Southern Italy)
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE Thalassia Salentina provided by ESE - Salento University Publishing Thalassia Sal. 41 (2019), 47-52 ISSN 0563-3745, e-ISSN 1591-0725 DOI 10.1285/i15910725v41p47 http: siba-ese.unisalento.it - © 2019 Università del Salento GIORGIO MANCINELLI1,2,3*, FRANCESCO BELMONTE4, GENUARIO BELMONTE1,3 1 Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, 73100 Lecce, Italy 2 National Research Council (CNR), Institute of Biological Resources and Marine Biotechnologies (IRBIM), Lesina - (FG), Italy 3 CoNISMa, Consorzio Nazionale Interuniversitario per le Scienze del Mare, 00196 Roma, Italy 4 via G. Casciaro, 73100 Lecce, Italy * corresponding author: [email protected] OCCURRENCE OF OCYPODE CURSOR (LINNAEUS, 1758) (CRUSTACEA, DECAPODA) IN SALENTO (SOUTHERN ITALY) SUMMARY Ocypode cursor (Linnaeus, 1758) is the only Ocypode species present in the Mediterranean Sea. It is widely distributed in the southern part of the basin (mainly African coast) and only recently it has been reported also from Sicil- ian Ionian sea. The present record is the first for Italian peninsula and the northernmost record of O. cursor in the Mediterranen Sea. INTRODUCTION The tufted ghost crab Ocypode cursor (Linnaeus, 1758) is a semi-terrestrial burrowing brachyuran of nocturnal habits generally found in supratidal and intertidal sandy beaches (STRACHAN et al., 1999). The species is the only member of the family Ocypodidae occurring in the Mediterranean Sea; specifically, it is characterized by a disjoint distribu- tion, comprising the eastern Mediterranean Sea and tropical coasts of the eastern Atlantic Ocean as far south as northern Namibia, with the exclusion of the western Mediterranean.
    [Show full text]
  • 17 the Crabs Belonging to the Grapsoidea Include a Lot Of
    17 SUPERFAMILY GRAPSOIDEA The crabs belonging to the Grapsoidea include a lot of ubiquitous species collected in the mangrove and/or along the coastline. As a result, most of the species listed here under the ‘Coastal Rock-rubble’ biotope of table 2b could be reasonably listed also with marine species. This is particularly true for the Grapsidae: Grapsus, Pachygrapsus, Pseudograpsus, and Thalassograpsus. FAMILY GECARCINIDAE Cardisoma carnifex (Herbst, 1796). Figure 12. – Cardisoma carnifex - Guinot, 1967: 289 (Checklist of WIO species, with mention of Grande Comore and Mayotte). - Bouchard, 2009: 6, 8, Mayotte, Malamani mangrove, 16 April 2008, St. 1, 12°55.337 S, 44°09.263 E, upper mangrove in shaded area, burrow, about 1.5 m depth, 1 male 61×74 mm (MNHN B32409). - KUW fieldwork November 2009, St. 6, Petite Terre, Badamiers spillway, upper littoral, 1 female 53×64 mm (MNHN B32410), 1 male 65×75.5 mm (MNHN B32411); St. 29, Ngouja hotel, Mboianatsa beach, in situ photographs only. Distribution. – Widespread in the IWP. Red Sea, Somalia, Kenya, Tanzania, Mozambique, South Africa, Europa, Madagascar, Comoros, Seychelles, Réunion, Mauritius, India, Taiwan, Japan, Australia, New Caledonia, Fiji, Wallis & Futuna, French Polynesia. Comment. – Gecarcinid land crabs are of large size and eaten in some places (West Indies, Wallis & Futuna, and French Polynesia). In Mayotte, however, they are not much prized for food and are not eaten. Figure 12. Cardisoma carnifex. Mayotte, KUW 2009 fieldwork: A) aspect of station 29, upper littoral Ngouja hotel, Mboianatsa beach; B) same, detail of a crab at the entrance of its burrow; C) St. 6, 1 female 53×64 mm (MNHN B32410); D) probably the same specimen, in situ at St.
    [Show full text]
  • Burrow Morphology of the Land Crab Gecarcinus Lateralis and the Ghost
    Smith ScholarWorks Geosciences: Faculty Publications Geosciences 1-2014 Burrow Morphology of the Land Crab Gecarcinus lateralis and the Ghost Crab Ocypode quadrata on San Salvador Island, The Bahamas: Comparisons and Palaeoenvironmental Implications Koji Seike University of Tokyo H. Allen Curran Smith College, [email protected] Follow this and additional works at: https://scholarworks.smith.edu/geo_facpubs Part of the Geology Commons Recommended Citation Seike, Koji and Curran, H. Allen, "Burrow Morphology of the Land Crab Gecarcinus lateralis and the Ghost Crab Ocypode quadrata on San Salvador Island, The Bahamas: Comparisons and Palaeoenvironmental Implications" (2014). Geosciences: Faculty Publications, Smith College, Northampton, MA. https://scholarworks.smith.edu/geo_facpubs/47 This Article has been accepted for inclusion in Geosciences: Faculty Publications by an authorized administrator of Smith ScholarWorks. For more information, please contact [email protected] SPANISH JOURNAL OF PALAEONTOLOGY Burrow morphology of the land crab Gecarcinus lateralis and the ghost crab Ocypode quadrata on San Salvador Island, The Bahamas: comparisons and palaeoenvironmental implications Koji SEIKE1* & H. Allen CURRAN2 1 Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, 277-8564, Japan; [email protected] 2 Department of Geosciences, Smith College, Northampton, Massachusetts, 01063, USA; [email protected] * Corresponding author Seike, K. & Curran, H.A. 2014. Burrow morphology of the land crab Gecarcinus lateralis and the ghost crab Ocypode quadrata on San Salvador Island, The Bahamas: comparisons and palaeoenvironmental implications [Morfologías de las madrigueras del cangrejo terrestre Gecarcinus lateralis y del cangrejo fantasma Ocypode quadrata en la isla de San Salvador (Bahamas): comparación e implicaciones paleoambientales].
    [Show full text]
  • Burrow Architectural Types of the Atlantic Ghost Crab, Ocypode Quadrata (Fabricius
    bioRxiv preprint doi: https://doi.org/10.1101/006098; this version posted July 25, 2014. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 Burrow architectural types of the Atlantic ghost crab, Ocypode quadrata (Fabricius, 2 1787) (Brachyura: Ocypodidae), in Brazil 3 4 WILLIAN T. A. F. SILVA1,2, TEREZA C. S. CALADO1 5 6 1Integrated Laboratories of Marine and Natural Sciences (LabMar), Federal University of 7 Alagoas (UFAL), Avenida Aristeu de Andrade, 452, Farol, CEP 57051-090, Maceió, 8 Alagoas, Brazil. 9 2Current affiliation: Department of Evolutionary Biology (Ecology and Genetics), 10 Evolutionary Biology Center (EBC), Uppsala University, Uppsala, Sweden. 11 Corresponding author: WTAFS, [email protected] 12 13 Running title: Shapes of ghost crab burrows 14 15 Abstract: A broad range of aspects from paleontology to physiology of the ghost crabs 16 Ocypode quadrata have been studied worldwide. These crabs have been used as ecological 17 indicators of the levels of anthropogenic impacts on sandy beaches. Our aim is to report the 18 variety of burrow architecture types constructed by ghost crabs Ocypode quadrata on 19 beaches of Maceió, Brazil. We found 20 types of burrows that differ in shape (number of 20 axes, number of openings, orientation of blind end, number of branches). The slash-shaped 21 burrows (type C) were the most frequent shape, followed by types K (spiral) and E (Y- 22 shaped).
    [Show full text]
  • Bioecology of the Ghost Crab Ocypode Quadrata (Fabricius, 1787) (Crustacea: Brachyura) Compared with Other Intertidal Crabs in the Southwestern Atlantic
    Journal of Shellfish Research, Vol. 29, No. 2, 503–512, 2010. BIOECOLOGY OF THE GHOST CRAB OCYPODE QUADRATA (FABRICIUS, 1787) (CRUSTACEA: BRACHYURA) COMPARED WITH OTHER INTERTIDAL CRABS IN THE SOUTHWESTERN ATLANTIC JOAQUIM O. BRANCO,1 JULIANO C. HILLESHEIM,1 HE´LIO A. A. FRACASSO,2 MARTIN L. CHRISTOFFERSEN3* AND CRISTIANO L. EVANGELISTA1 1Centro de Cieˆncias Tecnolo´gicas da Terra e do Mar (CTTMar), Universidade Vale do Itajaı´ (UNIVALI), CP 360, 88302-202 Itajaı´, SC, Brazil; 2Departamento de Hidrobiologia, Universidade Federal de Sa˜o Carlos (UFSCar), 13565-905, Sa˜o Carlos, SP, Brazil; 3Departamento de Sistema´tica e Ecologia, Universidade Federal da Paraı´ba, 58059-900, Joa˜o Pessoa, PB, Brazil ABSTRACT Data sets on the natural dynamics of beach ecosystems are scarce and fragmentary. Such data are necessary for implementing more efficient monitoring programs that quantify the dynamics of key ecological attributes on sandy beaches. This article contributes to the bioecology of ghost crabs from subtropical Praia Brava, Itajaı´, Santa Catarina. Ocypode quadrata occurs in sandy beaches along the tropical–temperate western Atlantic, from Rhode Island (US) to Rio Grande do Sul (Brazil). During 14 consecutive months, a total of 649 specimens were captured: 255 females (39%), 241 males (37%), and 153 juveniles of undetermined sex (24%). Highest densities were recorded in June and November, with a total of 1,900 burrows distributed along the beach (56.95%) and dunes (43.05%). Sixteen natural diet items were identified for this crab, with a larger participation of Apis spp. (38.97% of relative volume). In the local food web, the ground-burrowing owl Speotyto cunicularia was the main crab predator.
    [Show full text]
  • Assessing Anthropogenic and Natural Impacts on Ghost Crabs (Ocypode Quadrata) at Cape Hatteras National Seashore, North Carolina Carl H
    Journal of Coastal Research 24 6 1450–1458 West Palm Beach, Florida November 2008 Assessing Anthropogenic and Natural Impacts on Ghost Crabs (Ocypode quadrata) at Cape Hatteras National Seashore, North Carolina Carl H. Hobbs, III, Cynthia B. Landry*, and James E. Perry, III Virginia Institute of Marine Science College of William & Mary P.O. Box 1346 Gloucester Point, VA 23062-1346, U.S.A. [email protected] ABSTRACT HOBBS, C.H., III; LANDRY, C.B., and PERRY, J.E., III, 2008. Assessing anthropogenic and natural impacts on ghost crabs (Ocypode quadrata) at Cape Hatteras National Seashore, North Carolina. Journal of Coastal Research, 24(6), 1450–1458. West Palm Beach (Florida), ISSN 0749-0208. This study explores impacts of off-road vehicles on ghost crab populations as a measure of impact from recreational beach use on two beaches of the Cape Hatteras National Seashore and assesses the effectiveness of several alternatives for the use of off-road vehicles (ORVs) on the beach. Ghost crab population size and density have been used as indicators of the environmental quality of beaches and dunes. Data on the creation of an ‘‘ORV corridor’’ in which ORVs can drive on the landward portion of the berm, but not on the beach crest, indicate that it may be possible to preserve ghost crab populations on the beach while still permitting the use of ORVs. Closing the beach crest 24 hours a day may be the optimal solution for preservation of ghost crab populations. High-energy weather events, however, resulted in larger changes to the population dynamics of the ghost crabs.
    [Show full text]
  • Human Threats to Sandy Beaches – a Meta-Analysis of Ghost Crabs
    Estuarine, Coastal and Shelf Science 169 (2016) 56e73 Contents lists available at ScienceDirect Estuarine, Coastal and Shelf Science journal homepage: www.elsevier.com/locate/ecss Human threats to sandy beaches: A meta-analysis of ghost crabs illustrates global anthropogenic impacts. * Thomas A. Schlacher a, , Serena Lucrezi b, Rod M. Connolly c, Charles H. Peterson d, Ben L. Gilby a, Brooke Maslo e, Andrew D. Olds a, Simon J. Walker a, Javier X. Leon a, Chantal M. Huijbers a, Michael A. Weston f, Alexander Turra g, Glenn A. Hyndes h, Rebecca A. Holt c, David S. Schoeman a a School of Science and Engineering, The University of the Sunshine Coast, Q-4558, Maroochydore, Australia b TREESdTourism Research in Economic Environs and Society, North-West University, Potchefstroom, South Africa c Australian Rivers Institute e Coast & Estuaries, and School of Environment, Gold Coast Campus, Griffith University, Queensland, 4222, Australia d Institute of Marine Sciences, University of North Carolina, Chapel Hill, Morehead City, NC, 28557, USA e Department of Ecology, Evolution and Natural Resources Rutgers, The State University of New Jersey, USA f Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia g Departamento de Oceanografia Biologica, Instituto Oceanografico, Universidade de Sao~ Paulo, Praça do Oceanografico, 191, CEP 05508-120, Sao~ Paulo, SP, Brazil h Centre for Marine Ecosystems Research, Edith Cowan University, WA, Australia article info abstract Article history: Beach and coastal dune systems are increasingly subjected to a broad range of anthropogenic pressures Received 23 October 2015 that on many shorelines require significant conservation and mitigation interventions.
    [Show full text]
  • Patterns and Intensity of Ghost Crab Predation on the Nests of an 2 Important Endangered Loggerhead Turtle Population
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Digital.CSIC JEMBE-50488; No of Pages 8 Journal of Experimental Marine Biology and Ecology xxx (2015) xxx–xxx Contents lists available at ScienceDirect Journal of Experimental Marine Biology and Ecology journal homepage: www.elsevier.com/locate/jembe 1Q1 Patterns and intensity of ghost crab predation on the nests of an 2 important endangered loggerhead turtle population a, b b b c 3Q2 Adolfo Marco ⁎, Jesemine da Graça , Rosa García-Cerdá , Elena Abella , Rui Freitas 4 a Estación Biológica de Doñana, CSIC, C/Américo Vespucio s/n, 41092 Sevilla, Spain 5 b BIOS.CV, Sal Rei, Boa Vista Island, Cape Verde 6 c Departamento de Engenharias e Ciências do Mar, Universidade de Cape Verde, CP 163 Mindelo, Cape Verde 7 article info abstract 8 Article history: Predation is one of the most important threats to the early life stages of most endangered vertebrates. On small 20 9 Received 20 January 2015 oceanic islands that host very important endangered sea turtle rookeries, ghost crabs are the main nest predators. 21 10 Received in revised form 13 March 2015 Mortality in nests was evaluated on the island of Boa Vista which hosts around 75% of the nests in the Cape Verde 22 11 Accepted 14 March 2015 archipelago, which is one of the world's largest loggerhead turtle (Caretta caretta) rookeries. In an extensive 23 12 Available online xxxx survey of the island, egg mortality significantly varied between beaches and averaged 70%. One of the main 24 causes of egg mortality was predation by ghost crabs (Ocypode cursor) that stole an average of 33 eggs per 25 13 Keywords: fi 26 14 Cape Verde nest.
    [Show full text]
  • Ghost Crab Burrow Density at Watamu Marine National Park: an Indicator of the Impact of Urbanisation and Associated Disturbance?
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Nottingham Trent Institutional Repository (IRep) African Journal of Marine Science ISSN: 1814-232X (Print) 1814-2338 (Online) Journal homepage: http://www.tandfonline.com/loi/tams20 Ghost crab burrow density at Watamu Marine National Park: An indicator of the impact of urbanisation and associated disturbance? HFR Hereward, LK Gentle, ND Ray & RD Sluka To cite this article: HFR Hereward, LK Gentle, ND Ray & RD Sluka (2017) Ghost crab burrow density at Watamu Marine National Park: An indicator of the impact of urbanisation and associated disturbance?, African Journal of Marine Science, 39:1, 129-133, DOI: 10.2989/1814232X.2017.1305990 To link to this article: http://dx.doi.org/10.2989/1814232X.2017.1305990 Published online: 11 Jul 2017. Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=tams20 Download by: [Nottingham Trent University] Date: 11 July 2017, At: 08:41 African Journal of Marine Science 2017, 39(1): 129–133 Copyright © NISC (Pty) Ltd Printed in South Africa — All rights reserved AFRICAN JOURNAL OF MARINE SCIENCE ISSN 1814-232X EISSN 1814-2338 http://dx.doi.org/10.2989/1814232X.2017.1305990 Short communication Ghost crab burrow density at Watamu Marine National Park: An indicator of the impact of urbanisation and associated disturbance? HFR Hereward1,2,3*, LK Gentle1, ND Ray1 and RD Sluka2,4 1 School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Southwell, UK 2 A Rocha Kenya, Watamu, Kenya 3 Current address: A Rocha UK, Southall, UK 4 Marine and Coastal Conservation Programme, A Rocha International, London, UK * Corresponding author, e-mail: [email protected] Ghost crab (Ocypode species) burrow densities have previously been used as an indicator of anthropogenic impact.
    [Show full text]
  • Assessing the Critical Role That Land Crabs Play in Tropical Island Rodent Eradications and Ecological Restoration
    A. Samaniego-Herrera, S. Boudjelas, G.A. Harper, and J.C. Russell Samaniego-Herrera, A.; S. Boudjelas, G.A. Harper and J.C. Russell. Assessing the critical role that land crabs play in tropical island rodent eradications and ecological restoration Assessing the critical role that land crabs play in tropical island rodent eradications and ecological restoration A. Samaniego-Herrera1,2, S. Boudjelas2,3, G.A. Harper4 and J.C. Russell1 1School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand. <[email protected]>. 2Pacific Invasives Initiative, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand. 3Centre for Biodiversity and Biosecurity, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand. 4Biodiversity Restoration Specialists, PO Box 65, Murchison, New Zealand. Abstract Invasive rodent eradications are one of the most effective conservation interventions to restore island ecosystems. However, achievements in the tropics are lagging behind those in temperate regions. Land crab interference in bait uptake has been identified as one of the main causes of rodent eradication failure on tropical islands, but the issue of effective mitigation of bait loss due to land crab consumption is poorly understood. For example, there are over 100 species of land crab and each may behave differently. We reviewed the available literature to answer: (1) which crab species are the most problematic? (2) what mitigation measures have been effective? and (3) how do invasive rodents impact land crab communities? We analysed a systematic dataset from six tropical islands to test two hypotheses: (a) bait uptake is highest when burrowing (Brachyura) land crabs are present; and (b) small land crabs (including juveniles of the larger species) are highly vulnerable to rodent predation.
    [Show full text]