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Dias E, Morais P, Antunes C, Hoffman JC. The benthic food web connects the estuarine habitat mosaic to adjacent ecosystems. FOOD WEBS 2023; 35:e00282. [PMID: 37731992 PMCID: PMC10508047 DOI: 10.1016/j.fooweb.2023.e00282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Energy flows from land to sea and between pelagic and benthic environments have the potential to increase the connectivity between estuaries and adjacent ecosystems as well as among estuarine habitats. To identify such energy flows and the main trophic pathways of energy transfer in the Minho River estuary, we investigated the spatial and temporal fluctuations of carbon and nitrogen stable isotope ratios in benthic (and their potential food sources) and epibenthic consumers. Sampling was conducted along the estuarine salinity gradient from winter to summer of 2011. We found that the carbon (δ13C = 13C/12C) and nitrogen (δ15N = 15N/14N) stable isotope ratios of the most abundant benthic and epibenthic consumers varied along the salinity gradient. The δ13C values increased seaward, whereas the opposite pattern was found for the δ15N, especially during the summer. The stable isotope ratios revealed two trophic pathways in the Minho estuary food web. The first pathway is supported by phytoplankton and represented by filter feeders such as zooplankton and some deposit feeders, particularly amphipods and polychaetes. The second pathway is supported by detritus and composed essentially of deposit feeders, which by being consumed, allow detritus to be incorporated into higher trophic levels. Spatial and temporal feeding variations in the estuarine benthic food web are driven by hydrology and proximity to adjacent ecosystems (terrestrial, marine). During high river discharge periods, the δ13CPOC (ca. -28‰) and C: NPOM (>10) values suggested an increase of terrestrial-derived OM to the particulate OM pool, which was then used by suspension feeders. During low river discharge periods, marine intrusion increased upriver, which was reflected in benthic consumers' 13C-enriched stable isotope values. No relationship was found between food quality (phytoplankton vs. detritus) and food chain length because the lowest and highest values were associated with freshwater and saltmarsh areas, respectively, both dominated by the detrital pathway. This study demonstrates that benthic consumers enhance the connectivity between estuaries and its adjacent ecosystems by utilizing subsidies of terrestrial and marine origin and that benthic-pelagic coupling is an important energy transfer mechanism to the benthic food web.
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Affiliation(s)
- Ester Dias
- CIIMAR – Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida Norton de Matos, 4450-208 Matosinhos, Portugal
| | - Pedro Morais
- CCMAR – Centre of Marine Sciences, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Carlos Antunes
- CIIMAR – Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida Norton de Matos, 4450-208 Matosinhos, Portugal
- Aquamuseu do Rio Minho, Parque do Castelinho s/n, 4920-290 Vila Nova de Cerveira, Portugal
| | - Joel C. Hoffman
- Great Lakes Toxicology and Ecology Division, Center for Computational Toxicology and Exposure, US Environmental Protection Agency Office of Research and Development, 6201 Congdon Blvd, Duluth, MN 55804, USA
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Zhao J, Wen Y, Zhu S, Ye J, Zhu J, Ye Z, Jordan A. Solving post-prandial reduction in performance by adaptive regurgitation in a freshwater fish. Proc Biol Sci 2020; 287:20202172. [PMID: 33171081 DOI: 10.1098/rspb.2020.2172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Foraging animals must balance benefits of food acquisition with costs induced by a post-prandial reduction in performance. Eating to satiation can lead to a reduction in locomotor and escape performance, which increases risk should a threat subsequently arises, but limiting feeding behaviour may be maladaptive if food intake is unnecessarily reduced in the prediction of threats that do not arise. The efficacy of the trade-off between continued and interrupted feeding therefore relies on information about the future risk, which is imperfect. Here, we find that black carp (Mylopharyngodon piceus) can balance this trade-off using an a posteriori strategy; by eating to satiation but regurgitating already ingested food when a threat arises. While degrees of satiation (DS) equal to or greater than 60% reduce elements of escape performance (turning angle, angular velocity, distance moved, linear velocity), at 40% DS or lower, performance in these tasks approaches levels comparable to that at 0% satiation. After experiencing a chasing event, we find that fish are able to regurgitate already ingested food, thereby changing the amount of food in their gastrointestinal tract to consistent levels that maintain high escape performance. Remarkably, regurgitation results in degrees of satiation between 40 and 60% DS, regardless of whether they had previously fed to 40, 60 or 100% DS. Using this response, fish are able to maximize food intake, but regurgitate extra food to maintain escape performance when they encounter a threat. This novel strategy may be effective for continual grazers and species with imperfect information about the level of threat in their environment.
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Affiliation(s)
- Jian Zhao
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, People's Republic of China
| | - Yanci Wen
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, People's Republic of China
| | - Songming Zhu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, People's Republic of China.,Ocean Academy, Zhejiang University, Zhoushan, 316000, People's Republic of China
| | - Jinyun Ye
- School of Life Sciences, Huzhou University, Huzhou, 313000, People's Republic of China
| | - Junjie Zhu
- School of Life Sciences, Huzhou University, Huzhou, 313000, People's Republic of China
| | - Zhangying Ye
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310000, People's Republic of China.,Ocean Academy, Zhejiang University, Zhoushan, 316000, People's Republic of China
| | - Alex Jordan
- Department of Collective Behaviour, Max Planck Institute of Animal Behaviour, Konstanz, 78467, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, 78467, Germany
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3
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Mora-Obando D, Salazar-Valenzuela D, Pla D, Lomonte B, Guerrero-Vargas JA, Ayerbe S, Gibbs HL, Calvete JJ. Venom variation in Bothrops asper lineages from North-Western South America. J Proteomics 2020; 229:103945. [DOI: 10.1016/j.jprot.2020.103945] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/09/2020] [Accepted: 08/13/2020] [Indexed: 01/09/2023]
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4
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Diniz-Sousa R, Moraes JDN, Rodrigues-da-Silva TM, Oliveira CS, Caldeira CADS. A brief review on the natural history, venomics and the medical importance of bushmaster ( Lachesis) pit viper snakes. Toxicon X 2020; 7:100053. [PMID: 32793880 PMCID: PMC7408722 DOI: 10.1016/j.toxcx.2020.100053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/14/2020] [Accepted: 07/18/2020] [Indexed: 12/17/2022] Open
Abstract
Snakes of the genus Lachesis, commonly known as bushmasters, are the largest venomous snakes in the Americas. Because these snakes have their habitats in areas of remote forests they are difficult to find, and consequently there are few studies of Lachesis taxa in their natural ecosystems. Bushmasters are distributed in tropical forest areas of South and Central America. In Brazil they can be found in the Amazon Rainforest and the Atlantic Forest. Despite the low incidence of cases, laquetic envenoming causes severe permanent sequelae due to the high amount of inoculated venom. These accidents are characterized by local pain, hemorrhage and myonecrosis that can be confused with bothropic envenomings. However, victims of Lachesis bites develop symptoms characteristic of Lachesis envenoming, known as vagal syndrome. An important message of this bibliographic synthesis exercise is that, despite having the proteomic profiles of all the taxa of the genus available, very few structure-function correlation studies have been carried out. Therefore the motivation for this review was to fill a gap in the literature on the genus Lachesis, about which there is no recent review. Here we discuss data scattered in a number of original articles published in specialized journals, spanning the evolutionary history and extant phylogeographic distribution of the bushmasters, their venom composition and diet, as well as the pathophysiology of their bites to humans and the biological activities and possible biotechnological applicability of their venom toxins.
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Affiliation(s)
- Rafaela Diniz-Sousa
- Center for the Study of Biomolecules Applied to Health (CEBio), Oswaldo Cruz Foundation Rondônia, Porto Velho, RO, Brazil
- Graduate Program in Experimental Biology (PGBIOEXP), Federal University of Rondônia (UNIR), Porto Velho, RO, Brazil
- Sao Lucas University Center (UniSL), Porto Velho, RO, Brazil
| | - Jeane do N. Moraes
- Center for the Study of Biomolecules Applied to Health (CEBio), Oswaldo Cruz Foundation Rondônia, Porto Velho, RO, Brazil
- Graduate Program in Experimental Biology (PGBIOEXP), Federal University of Rondônia (UNIR), Porto Velho, RO, Brazil
| | | | - Cláudia S. Oliveira
- Center for the Study of Biomolecules Applied to Health (CEBio), Oswaldo Cruz Foundation Rondônia, Porto Velho, RO, Brazil
- Graduate Program in Experimental Biology (PGBIOEXP), Federal University of Rondônia (UNIR), Porto Velho, RO, Brazil
| | - Cleópatra A. da S. Caldeira
- Center for the Study of Biomolecules Applied to Health (CEBio), Oswaldo Cruz Foundation Rondônia, Porto Velho, RO, Brazil
- Graduate Program in Experimental Biology (PGBIOEXP), Federal University of Rondônia (UNIR), Porto Velho, RO, Brazil
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Lomonte B, Díaz C, Chaves F, Fernández J, Ruiz M, Salas M, Zavaleta A, Calvete JJ, Sasa M. Comparative characterization of Viperidae snake venoms from Perú reveals two compositional patterns of phospholipase A 2 expression. Toxicon X 2020; 7:100044. [PMID: 32550596 PMCID: PMC7285926 DOI: 10.1016/j.toxcx.2020.100044] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 05/09/2020] [Accepted: 05/25/2020] [Indexed: 12/16/2022] Open
Abstract
Snake species within the Bothrops complex (sensu lato) are of medical relevance in Latin America, but knowledge on their venom characteristics is limited, or even unavailable, for some taxa. Perú harbors 17 species of pit vipers, within the genera Bothrops, Bothriechis, Bothrocophias, Porthidium, Crotalus, and Lachesis. This study compared the venoms of twelve species, through chromatographic and electrophoretic profiles, as well as proteolytic and phospholipase A2 (PLA2) activities. Also, proteomic profiles were analyzed for nine of the venoms using a shotgun approach. Results unveiled conspicuous differences in the expression of venom PLA2s among species, six of them presenting scarce levels as judged by RP-HPLC profiles. Since most species within the bothropoid lineage possess venoms with high to intermediate abundances of this protein family, our findings suggest the existence of a phenotypic duality in the expression of venom PLA2s within the Bothrops (sensu lato) complex. Bothrops barnetti and Bothrocophias andianus venoms, very scarce in PLA2s, were shown to lack significant myotoxic activity, highlighting that the observed variability in PLA2 expression bears toxicological correlations with effects attributed to these proteins. Finally, an attempt to identify phylogenetic relationships of bothropoid species from Perú presenting low- or high-PLA2 venom phenotypes showed an interspersed pattern, thus precluding a simple phylogenetic interpretation of this venom compositional dichotomy. Venoms from 12 viperids of Perú were compared. Conspicuous differences in the expression of PLA2 were found. Venoms presenting scarce levels of PLA2 lack myotoxicity. A new phenotypic dichotomy in venom PLA2 expression is described within Bothrops (sensu lato).
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Affiliation(s)
- Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Cecilia Díaz
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica.,Departamento de Bioquímica, Escuela de Medicina, Universidad de Costa Rica, San José, Costa Rica
| | - Fernando Chaves
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Julián Fernández
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Marco Ruiz
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - María Salas
- Departamento Académico de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Alfonso Zavaleta
- Departamento Académico de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Juan J Calvete
- Laboratorio de Venómica Evolutiva y Traslacional, Instituto de Biomedicina de Valencia, CSIC, Valencia, Spain
| | - Mahmood Sasa
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica.,Escuela de Biología, Universidad de Costa Rica, San José, Costa Rica
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Sánchez-Hernández J, Nunn AD, Adams CE, Amundsen PA. Causes and consequences of ontogenetic dietary shifts: a global synthesis using fish models. Biol Rev Camb Philos Soc 2018; 94:539-554. [DOI: 10.1111/brv.12468] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 08/24/2018] [Accepted: 08/30/2018] [Indexed: 02/01/2023]
Affiliation(s)
- Javier Sánchez-Hernández
- Departamento de Zooloxía, Xenética e Antropoloxía Física, Facultade de Bioloxía; Universidade de Santiago de Compostela; Campus Vida s/n, 15782, Santiago de Compostela Spain
| | - Andy D. Nunn
- Hull International Fisheries Institute, School of Environmental Sciences; University of Hull; Hull, HU6 7RX UK
| | - Colin E. Adams
- Scottish Centre for Ecology and the Natural Environment, Institute of Biodiversity; Animal Health and Comparative Medicine, University of Glasgow; Rowardennan, Glasgow, G63 0AW UK
| | - Per-Arne Amundsen
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics; UiT The Arctic University of Norway; N-9037, Tromsø Norway
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7
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Schwerdt L, Pompozzi G, de Villalobos AE, Pérez-Miles F. Trophic traits of Grammostola vachoni, a tarantula (Araneae : Theraphosidae) from Argentina. AUST J ZOOL 2018. [DOI: 10.1071/zo18034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This is the first study about trophic traits of Grammostola vachoni, a threatened theraphosid spider endemic to the mountain systems of central Argentina. Four prey types were used in experiments: crickets, cockroaches, beetle larvae and adult beetles. Grammostola vachoni was observed to eat at a rate of about once every 11 days, with the mean total number of prey consumed per spider during the experimental period being 2.7. Latency to the first attack was similar for crickets, cockroaches and beetle larvae, but was shorter for adult beetles. Feeding time was significantly longer for crickets and beetle larvae. Mass gain was significantly different among prey types. Feeding effectiveness and ingestion rate were significantly higher for crickets. A significant positive correlation for feeding effectiveness and ingestion rate with prey mass and the initial spider mass was also found.
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8
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Norin T, Clark TD. Fish face a trade-off between 'eating big' for growth efficiency and 'eating small' to retain aerobic capacity. Biol Lett 2017; 13:rsbl.2017.0298. [PMID: 28931728 DOI: 10.1098/rsbl.2017.0298] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/31/2017] [Indexed: 11/12/2022] Open
Abstract
Feeding provides the necessary energy to fuel all fitness-related processes including activity, growth and reproduction. Nevertheless, prey consumption and digestive processes can have physical and physiological trade-offs with other critical functions, many of which are not clearly understood. Using an ambush predator, barramundi (Lates calcarifer), fed meals ranging 0.6-3.4% of body mass, we examined interrelations between meal size, growth efficiency and surplus aerobic metabolic capacity (aerobic scope, AS). Large meals required a greater absolute investment of energy to process (a larger so-called specific dynamic action, SDA), but the percentage of digestible meal energy required in the SDA response (SDA coefficient) decreased with increasing meal size. Combined with the findings that growth rate and growth efficiency also increased with food intake, our results demonstrate that it is energetically advantageous for fish to select large prey. However, following a large meal, SDA processes occupied up to 77% of the available AS, indicating that other oxygen-demanding activities like swimming may be compromised while large meals are processed. This trade-off between meal size and AS suggests that fishes like barramundi would benefit from regulating prey size based on imminent requirements and threats.
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Affiliation(s)
- Tommy Norin
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Timothy D Clark
- University of Tasmania Institute for Marine and Antarctic Studies, and CSIRO Agriculture and Food, Hobart, Tasmania 7000, Australia
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9
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Catania S, Koprivnikar J, McCauley S. Size-dependent predation alters interactions between parasites and predators. CAN J ZOOL 2016. [DOI: 10.1139/cjz-2016-0088] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Increasing evidence indicates that parasites play an important role within many systems as prey for higher trophic levels. Predation on parasites can decrease their numbers and may affect host infection rates. Cercariae, a free-living infectious stage of trematode parasites, are abundant in freshwater systems and are directly consumed by a number of freshwater predators. However, few studies have tested whether predators exhibit a preference for cercariae when alternative prey are available or how these preferences vary across predator body sizes. We assessed whether dragonfly larvae (dot-tailed whiteface, Leucorrhinia intacta (Hagen, 1861)), top predators in freshwater systems without fish, foraged preferentially when presented with two prey types, cercariae and zooplankton, and whether foraging preferences changed across predator body size. Body size of larval dragonfly predators was found to be significantly, and negatively, related to the fraction of cercariae in the diet. Larger bodied dragonfly larvae shifted their diet choice from cercariae to zooplankton. Changes in foraging selectivity as body size increases across a predator’s ontogeny can alter the strength of predator–prey interactions. Further investigation into size-selective foraging on parasites may provide new insights into the effects of predation on parasite abundance and transmission in natural systems.
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Affiliation(s)
- S.V.L. Catania
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
| | - J. Koprivnikar
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
| | - S.J. McCauley
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
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10
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Wollrab S, de Roos AM, Diehl S. Ontogenetic diet shifts promote predator-mediated coexistence. Ecology 2013; 94:2886-97. [DOI: 10.1890/12-1490.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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11
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Chargulaf CA, Krück NC, Tibbetts IR. Does sympatry affect trophic resource use in congeneric tidepool fishes? A tale of two gobies Favonigobius lentiginosus and Favonigobius exquisitus. JOURNAL OF FISH BIOLOGY 2011; 79:1968-1983. [PMID: 22141899 DOI: 10.1111/j.1095-8649.2011.03132.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The feeding ecology of two sympatric gobies, Favonigobius lentiginosus and Favonigobius exquisitus, which inhabit soft substrate pools was studied in Moreton Bay, Australia. Favonigobius spp. and sediment cores were collected from three locations within the bay and fish gut contents were analysed to explore potential competition and ontogenetic dietary shifts. The most abundant prey at all sites was nematodes at 6.33 ± 0.38 cm(-3) at Dunwich, 33.58 ± 0.26 cm(-3) at Manly and 6.36 ± 0.849 cm(-3) (mean ± S.E.) at Godwin Beach. Nevertheless, they were not a dominant component of the diets. Volumetric percent contribution of prey showed that copepods and decapod shrimps dominated F. lentiginosus diets at Dunwich (7.8 and 6.6%, respectively) and Godwin Beach (6.5 and 14.3%, respectively) and the diets of F. exquisitus at Manly (9.2 and 9.5%, respectively) and Godwin Beach (10.4 and 11.8%, respectively). Schoener's index of dietary overlap between the two species, when sympatric, was 0.85 indicating a high similarity. An ontogenetic shift towards larger prey items occurred as Favonigobius spp. reached larger sizes. Gut fullness indices showed significant differences between time of day (two-way ANOVA, P < 0.01) and species (two-way ANOVA, P < 0.05) but Bonferroni's multiple comparison test showed that the only significant difference was between F. lentiginosus at Dunwich and F. exquisitus at Godwin Beach at 1800 hours. Food resource competition and temporal resource partitioning did not appear to be a limiting factor between F. lentiginosus and F. exquisitus despite cohabitation in such restricted environments.
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Affiliation(s)
- C A Chargulaf
- School of Biological Sciences, The University of Queensland, St Lucia, Qld 4072, Australia.
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Philip BN, Shillington C. The effect of prey availability on metabolism and activity in the tarantulaPhormictopus cancerides. CAN J ZOOL 2010. [DOI: 10.1139/z09-122] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spiders typically exhibit very low resting metabolic rates (RMR) and altered feeding behaviors as mechanisms to survive extended periods of limited food availability. We examined the effect of different periods of food deprivation on RMR and foraging activities in the Hispaniolan giant tarantula ( Phormictopus cancerides (Latreille, 1806)) (Araneae: Theraphosidae). Juvenile tarantulas were separated into two feeding groups and fed once either every 5 or 30 days. Monthly feeding trials were preceded by RMR measurements. During feeding trials, we compared differences between the two groups in (i) prey capture frequency, (ii) time to prey capture, (iii) locomotory activity, and (iv) the predator’s prey detection distance. Metabolic rates increased for the well-fed group but remained constant for individuals fed once a month. Time to prey capture decreased for food-limited individuals and the proportion of individuals that ate during each feeding trial was significantly higher in the 30-day group. Conversely, results for locomotory activity and detection distances were inconclusive.
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Affiliation(s)
- B. N. Philip
- Department of Biology, Eastern Michigan University, Ypsilanti, MI 48197, USA
| | - C. Shillington
- Department of Biology, Eastern Michigan University, Ypsilanti, MI 48197, USA
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