Size-mediated, density-dependent cannibalism in the signal crayfish Pacifastacus leniusculus (Dana, 1852) (Decapoda, Astacidea), an invasive crayfish in Britain

in Crustaceana
Restricted Access
Get Access to Full Text
Rent on DeepDyve

Have an Access Token?

Enter your access token to activate and access content online.

Please login and go to your personal user account to enter your access token.


Have Institutional Access?

Access content through your institution. Any other coaching guidance?


The role of cannibalism in crayfish populations is not well understood, despite being a potentially key density-dependent process underpinning population dynamics. We studied the incidence of cannibalism in an introduced signal crayfish Pacifastacus leniusculus population in a Scottish lowland river in September 2014. Animals were sampled using six different sampling techniques simultaneously, revealing variable densities and size distributions across the site. Cannibalism prevalence was estimated by analysing the gut contents of crayfish >20 mm CL for the presence of crayfish fragments, which was found to be 20% of dissected individuals. When seeking evidence of relationships between the sizes of cannibals and ‘prey’, the density of conspecifics <56% the size of a dissected individual yielded the best fit. The relationship between cannibalism probability and crayfish size and density was equally well described by three different metrics of crayfish density. Cannibalism increased with crayfish size and density but did not vary according to sex. These results suggest that large P. leniusculus frequently cannibalize smaller (prey) conspecifics, and that the probability of cannibalism is dependent upon the relative size of cannibal-to-prey and the density of the smaller crayfish. We suggest that removing large individuals, as targeted by many traditional removal techniques, may lead to reduced cannibalism and therefore a compensatory increase in juvenile survival.


International Journal of Crustacean Research



AbrahamssonS. A. A., 1966. Dynamics of an isolated population of the crayfish Astacus astacus Linné. Oikos, 17: 96-107.

AcostaC. A.PerryS. A., 2000. Effective sampling area: a quantitative method for sampling crayfish populations in freshwater marshes. Crustaceana, 73: 425-431.

AlcorloP.GeigerW.OteroM., 2004. Feeding preferences and food selection of the red swamp crayfish, Procambarus clarkii, in habitats differing in food item diversity. Crustaceana, 77: 435-453.

BarasE.JoblingM., 2002. Dynamics of intracohort cannibalism in cultured fish. Aquaculture Res., 33: 461-479.

BartonK., 2014. MuMIn: Multi-Model Inference. Published by the author.

BatesD.MaechlerM.BolkerB.WalkerS.ChristensenR.SingmannH.DaiB.GrothendieckG.GreenP., 2014. lme4: linear mixed-effects models using Eigen and S4. R package version 1.1-7. (R Foundation for Statistical Computing, Vienna).

BondarC. A.BottriellK.ZeronK.RichardsonJ. S., 2005. Does trophic position of the omnivorous signal crayfish (Pacifastacus leniusculus) in a stream food web vary with life history stage or density? Can. J. Fish. Aquat. Sci., 62: 2632-2639.

BrittonJ. C.MortonB., 1994. Marine carrion and scavengers. Oceanogr. Mar. Biol. Annu. Rev., 32: 369-434.

CapelliG. M., 1980. Seasonal variation in the food habits of the crayfish Orconectes propinquus (Girard) in Trout Lake, Vilas County, Wisconsin, U.S.A. (Decapoda, Astacidea, Cambaridae). Crustaceana, 38: 82-86.

DanaE. D.López-SantiagoJ.García-de-LomasJ.García-OcañaD. M.GámezV.OrtegaF., 2010. Long-term management of the invasive Pacifastacus leniusculus (Dana, 1852) in a small mountain stream. Aquat. Invasions, 5: 317-322.

DistefanoA. R. J.GaleC. M.WagnerB. A.ZweifelR. D., 2003. A sampling method to assess lotic crayfish communities. J. Crustacean Biol., 23: 678-690.

DornN. J.UrgellesR.TrexlerJ. C., 2005. Evaluating active and passive sampling methods to quantify crayfish density in a freshwater wetland. J. North Am. Benthological Soc., 24: 346-356.

FarhadiA.GardnerC.KochanianP., 2014. Reducing cannibalism of narrow clawed crayfish Astacus leptodactylus Eschscholtz 1823 through management of photoperiod and stocking density. Asian Fish. Sci., 27: 286-296.

FarhadiA.JensenM. A., 2015. Effects of photoperiod and stocking density on survival, growth and physiological responses of narrow clawed crayfish (Astacus leptodactylus). Aquaculture Res., 47: 2518-2527.

FjällingA. B., 2011. The enclosure trap, a new tool for sampling juvenile crayfish. Knowl. Manag. Aquat. Ecosyst., 401: 9.

FreemanM. A.TurnbullJ. F.YeomansW. E.BeanC. W., 2010. Prospects for management strategies of invasive crayfish populations with an emphasis on biological control. Aquat. Conserv. Mar. Freshw. Ecosyst., 20: 211-223.

GardmarkA.JonzenN.MangelM., 2006. Density-dependent body growth reduces the potential of marine reserves to enhance yields. J Appl. Ecol., 43: 61-69.

GladmanZ. F.YeomansW. E.AdamsC. E.BeanC. W.McCollD.OlszewskaJ. P.McGillivrayC. W.McCluskeyR., 2010. Detecting North American signal crayfish (Pacifastacus leniusculus) in riffles. Aquat. Conserv. Mar. Freshw. Ecosyst., 20: 588-594.

GuanR. Z.WilesP. R., 1998. Feeding ecology of the signal crayfish Pacifastacus leniusculus in a British lowland river. Aquaculture, 169: 177-193.

GutheryF. S.ShawJ. H., 2013. Density dependence: applications in wildlife management. J. Wildl. Manage., 77: 33-38.

Gutierrez-YurritaP. J.SanchoG.BravoM. Á.BaltanásÁ.MontesC., 1998. Diet of the red swamp crayfish Procambarus clarkii in natural ecosystems of the Donana National Park temporary fresh-water marsh (Spain). J. Crustacean Biol., 18: 120-127.

HixonM. A.CarrM. H., 1997. Synergistic predation, density dependence, and population regulation in marine fish. Science, 277: 946-949.

JohnsenS. I.SkurdalJ.TaugbolT.GarnasE., 2014. Effect of mesh size on baited trap catch composition for noble crayfish (Astacus astacus). Knowl. Manag. Aquat. Ecosyst., 413: 6.

JonesJ. P. G.CoulsonT., 2006. Population regulation and demography in a harvested freshwater crayfish from Madagascar. Oikos, 112: 602-611.

LeeS. Y., 1995. Cheliped size and structure: the evolution of a multi-functional decapod organ. J. Exp. Mar. Biol. Ecol., 193: 161-176.

LovrichG. A.Sainte-MarieB., 1997. Cannibalism in the snow crab, Chionoecetes opilio (O. Fabricius) (Brachyura: Majidae), and its potential importance to recruitment. J. Exp. Mar. Biol. Ecol., 211: 225-245.

MoksnesP. O., 2004. Self-regulating mechanisms in cannibalistic populations of juvenile shore crabs Carcinus maenas. Ecology, 85: 1343-1354.

NyströmP., 2002. Ecology. In: HoldichD. M. (ed.), Biology of freshwater crayfish: 192-235. (MPG Books, Bodmin).

ParkynS. M.DiStefanoR. J.ImhoffE. M., 2011. Comparison of constructed microhabitat and baited traps in Table Rock reservoir, Missouri, U.S.A. Freshw. Crayfish, 18: 69-74.

PerssonL.ClaessenD.De RoosA. M.ByströmP.SjögrenS.SvanbäckR.WahlströmE.WestmanE., 2004. Cannibalism in a size-structured population: energy extraction and control. Ecol. Monogr., 74: 135-157.

PolicarT.KozákP., 2005. Comparison of trap and baited stick catch efficiency for noble crayfish (Astacus astacus L.) in the course of the growing season. Bull. Fr. Pêche Piscic., 376-377: 675-686.

PolisG. A., 1981. The evolution and dynamics of intraspecific predation. Annual. Rev. Ecol. Syst., 12: 225-251.

PostJ. R.ParkinsonE. A.JohnstonN. T., 1999. Density-dependent processes in structured fish populations: interaction strengths in whole-lake experiments. Ecol. Monogr., 69: 155-175.

PriceJ. E.WelchS. M., 2009. Semi-quantitative methods for crayfish sampling: sex, size, and habitat bias. J. Crustacean Biol., 29: 208-216.

R Core Team, 2013. R: a language and environment for statistical computing. (R Foundation for Statistical Computing, Vienna).

RabeniC. F.CollierK. J.ParkynS. M.HicksB. J., 1997. Evaluating techniques for sampling stream crayfish (Paranephrops planifrons). N. Z. J. Mar. Freshw. Res., 31: 693-700.

RahelF. J.SteinR. A., 1988. Complex predator-prey interactions and predator intimidation among crayfish, piscivorous fish, and small benthic fish. Oecologia, 75: 94-98.

ReynoldsJ. D., 2011. A review of ecological interactions between crayfish and fish, indigenous and introduced. Knowl. Manag. Aquat. Ecosyst., 401: 10.

ReynoldsJ. D.O’KeeffeC., 2005. Dietary patterns in stream- and lake-dwelling populations of Austropotamobius pallipes. Bull. Fr. Pêche Piscic., 376-377: 715-730.

SadykovaD.SkurdalJ.SadykovA.TaugbolT.HessenD. O., 2009. Modelling crayfish population dynamics using catch data: a size-structured model. Ecol. Model, 220: 2727-2733.

SavolainenR.RuohonenK.RailoE., 2004. Effect of stocking density on growth, survival and cheliped injuries of stage 2 juvenile signal crayfish Pasifastacus leniusculus Dana. Aquaculture, 231: 237-248.

SavolainenR.RuohonenK.TulonenJ., 2003. Effects of bottom substrate and presence of shelter in experimental tanks on growth and survival of signal crayfish Pasifastacus leniusculus (Dana) juveniles. Aquaculture Res., 34: 289-297.

ScaliciM.GibertiniG., 2009. Molt and gastroliths in Austropotamobius pallipes (Lereboullet, 1858). Knowl. Managt. Aquat. Ecosyst., 394-395: 14.

SinclairC. A., 2010. Fine scale mapping of signal crayfish distribution in Scotland, Scottish Natural Heritage Commissioned Report, Project 26686. (Scottish Natural Heritage, Inverness).

SomersK. M.StecheyD. P. M., 1986. Variable trappability of crayfish associated with bait type, water temperature and lunar phase. Am. Midl. Nat., 116: 36-44.

TwardochlebL. A.OldenJ. D.LarsonE. R., 2013. A global meta-analysis of the ecological impacts of nonnative crayfish. Freshw. Sci., 32: 1367-1382.

UlikowskiD.KrzywoszT.ŚmietanaP., 2006. A comparison of survival and growth in juvenile Astacus leptodactylus (Esch.) and Pacifastacus leniusculus (Dana) under controlled conditions. Bull. Fr. Pêche Piscic., 380-381: 1245-1253.

VollestadL. A.JonssonB., 1988. A 13-year study of the population dynamics and growth of the European eel Anguilla anguilla in a Norwegian river: evidence for density-dependent mortality, and development of a model for predicting yield. J. Anim. Ecol., 57: 983-997.

WagenmakersE. J.FarrellS., 2004. AIC model selection using Akaike weights. Psychon. Bull. Rev., 11: 192-196.

WoosterD.SynderJ. L.MadsenA., 2012. Environmental correlates of signal crayfish, Pacifastacus leniusculus (Dana, 1852), density and size at two spatial scales in its native range. J. Crustacean Biol., 32: 741-752.

WutzS.GeistJ., 2013. Sex- and size-specific migration patterns and habitat preference of invasive signal crayfish (Pacifastacus leniusculus Dana). Limnologica, 43: 59-66.

ZipkinE. F.CraftC. E.CoochE. G.SullivanP. J., 2009. When can efforts to control nuisance and invasive species backfire? Ecol. Appl., 19: 1585-1595.


  • A, size frequency distribution of carapace length (mm) for all crayfish captured from the Geddes Burn site; B, the catch number of small (<30 mm CL) and large (>30 mm CL) crayfish from downstream (section A) to upstream (section H); C, the proportion of substrate composition and mean midstream depths of each section from A-H.

    View in gallery
  • Likelihood profile of prey density with varying predator to prey size relationships. The black plots indicate AIC scores within two units of the lowest AIC score.

    View in gallery
  • A, the back-transformed effect of log(smaller prey density) on cannibalism probability taken from model 1; B, the effect of individual carapace length on cannibalism probability taken from model 2; C, the back-transformed effect of log(small crayfish density) on cannibalism probability taken from model 2; D, the effect of individual carapace length on cannibalism probability taken from model 3; E, the back-transformed effect of log(total crayfish density) on cannibalism probability taken from model 3; F, the effect of small crayfish density on cannibalism probability taken from model 4. The shaded area indicates 95% confidence intervals.

    View in gallery
  • A, Correlation between minnow trap and refuge trap catch number; B, correlation between minnow trap and cylindrical net trap catch number; C, correlation between refuge trap and cylindrical net trap catch number; D, correlation between electrofishing and microhabitat trap catch number; E, correlation between electrofishing and kick sampling catch number; F, correlation between microhabitat trap and kick sampling catch number.

    View in gallery
  • A, Correlation between mean minnow trap captured crayfish size (CL) and water depth; B, correlation between mean refuge trap captured crayfish size (CL) and water depth; C, correlation between mean cylindrical net trap captured crayfish size (CL) and water depth; D, correlation between mean electrofishing captured crayfish size (CL) and water depth; E, correlation between mean kick sampling captured crayfish size (CL) and water depth; F, correlation between mean habitat trap captured crayfish size (CL) and water depth.

    View in gallery


Content Metrics

Content Metrics

All Time Past Year Past 30 Days
Abstract Views 26 26 14
Full Text Views 6 6 6
PDF Downloads 1 1 1
EPUB Downloads 0 0 0