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Start Over Subject prey size estimation

1. On the use of diagnostic bones of brown trout, Salmo trutta m. fario, grayling, Thymallus thymallus and Carpathian sculpin, Cottus poecilopus in Eurasian otter, Lutra lutra diet analysis

Creator:
Hájková, Petra, Roche, Kevin, and Kocian, Ľudovít
Type:
article and TEXT
Subject:
prey size estimation, biomass, regression, and spraint analysis
Language:
English
Description:
Bones were obtained from three fish species (brown trout Salmo trutta m. fario, grayling Thymallus thymallus and Carpathian sculpin Cottus poecilopus) for regression analysis. Bones used were chosen based upon frequency of occurrence in spraint samples and diagnostic value. Relationships between the length of diagnostic bones and fish length, fish length and weight, and standard length to total length, were assessed for the three fish species. Polynomial regression was deemed most suitable for the relationship between bone length and fish standard length, multiplicative between fish standard length and fish weight, and linear (brown trout) or polynomial (grayling and Carpathian sculpin) for standard length against total length. All calculated regressions were highly significant and displayed high coefficients of determination, ranging between 93.9 and 99.8 %. The uses of the bones examined, and the equations produced, are discussed in the light of their future use in estimating prey numbers, length and biomass in otter diet analysis.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

2. Use of bone and otolith measures for size-estimation of fish in predator-prey studies

Creator:
Tarkan, Ali Serhan, Gürsoy Gaygusuz, Çiğdem, Gaygusuz, Özcan, and Acipinar, Hasan
Type:
article and TEXT
Subject:
diet analysis, prey size estimation, piscivorous predators, and cyprinids
Language:
English
Description:
To estimate the size of fish taken as prey by piscivorous predators, linear or non-linear relationships between bone measures (pharyngeal, opercula, cleithra, anal and dorsal spine bones, otoliths) and body length were elaborated for eleven Eurasian cyprinid fish species captured in three lakes of Turkey: rudd Scardinius erythrophthalmus, Baltic vimba Vimba vimba, Danube bleak Chalcalburnus chalcoides, gibel carp Carassius gibelio, roach Rutilus rutilus, silver bream Blicca bjoerkna, common carp Cyprinus carpio, chub Leuciscus cephalus, Dnieper chub Petroleuciscus borysthenicus, tench Tinca tinca and tarek Alburnus tarichi (endemic species for Lake Van). All calculated regressions were highly significant, with coefficients of determination >81% in most of cases. The results suggest that the biometric relationships between fish length and some bones (pharyngeal, opercula, cleithra) are well suited for use in prey-predator studies of all the studied species, but otoliths and the dorsal and anal spines can be used for some fish species only (rudd, Baltic vimba, roach, silver bream, gibel carp).
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/