Table 1
General linear model (GLM) analysis on the effect of fish size (standard length classes, L1-3), lake area (I − Keszthely, II − Szemes, III − Siófok basin), habitat (shore, offshore) and season (spring − Sp, summer − S, autumn − A) of stocking on the length increment (ΔL) of common carp and pikeperch in Lake Balaton, with days (d) or degree-day sum at 8 °C threshold water temperature (D8 °C) as covariant. Since size of the stocked fish varied between seasons, thus when the full GLM indicated a seasonal variability, main effect of season was also tested for each size group separately. Effect of the recapture area and interaction of stocking area × recapture area is also shown on ΔL at covariates d and D. Note that since factor interactions, except the marginal effect of fish size × season (P = 0.045) in common carp at covariant d, proved to be insignificant at P < 0.05, these results are not presented. Results of the Tukey HSD post hoc tests are also shown for significant factor effects.
| Common carp | Pikeperch | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ΔL vs. d | ΔL vs. D8 °C | ΔL vs. d | ΔL vs. D8 °C | |||||||||||||
| d.f. | F | P | Tukey HSD | d.f. | F | P | Tukey HSD | d.f. | F | P | Tukey HSD | d.f. | F | P | Tukey HSD | |
| Covariant: d | 1 | 962.2 | <0.001 | – | – | – | 1 | 962.7 | <0.001 | – | – | – | ||||
| Covariant: D8 °C | – | – | – | 1 | 1040.8 | <0.001 | – | – | – | 1 | 1082.9 | <0.001 | ||||
| Stocking fish size | 2 | 11.4 | <0.001 | L3 < L2 < L1 | 2 | 9.4 | <0.001 | L3 < L2 < L1 | 2 | 6.8 | 0.001 | L3 < L2 < L1 | 2 | 9.7 | <0.001 | L3 < L2 < L1 |
| Stocking lake area | 2 | 0.1 | 0.863 | 2 | 0.1 | 0.944 | 2 | 1.9 | 0.148 | 2 | 2.6 | 0.076 | ||||
| Stocking habitat | 1 | 1.6 | 0.202 | 1 | 0.8 | 0.386 | 1 | 2.6 | 0.109 | 1 | 2.1 | 0.152 | ||||
| Stocking season | 2 | 7.5 | <0.001 | S < Sp < A | 2 | 0.2 | 0.843 | 1 | 12.4 | <0.001 | NS | 1 | 0.0 | 0.867 | ||
| Error | 629 | 629 | 474 | 474 | ||||||||||||
| Main effect of stocking season by size groups | ||||||||||||||||
| L1 (≤245 mm) | 2;157 | 0.4 | 0.680 | 1;160 | 4.4 | 0.037 | NS | |||||||||
| L2 (246–265 mm) | 2;212 | 1.6 | 0.202 | 1;152 | 2.5 | 0.117 | ||||||||||
| L3 (>265 mm) | 2;258 | 11.3 | <0.001 | S<Sp, A | 1;160 | 5.5 | 0.021 | NS | ||||||||
| Effect of recapture area | ||||||||||||||||
| Covariant: d | 1 | 1086.5 | <0.001 | – | – | – | 1 | 1000.0 | <0.001 | – | – | – | ||||
| Covariant: D8°C | – | – | – | 1 | 1177.1 | <0.001 | – | – | – | 1 | 1142.1 | <0.001 | ||||
| Stocking lake area | 2 | 2.4 | 0.095 | 2 | 1.2 | 0.310 | 2 | 0.0 | 0.996 | 2 | 0.0 | 0.961 | ||||
| Recapture lake area | 2 | 2.3 | 0.102 | 2 | 0.8 | 0.432 | 2 | 3.5 | 0.031 | III<II, I | 2 | 2.9 | 0.054 | |||
| Stocking area × recapture area | 4 | 1.3 | 0.288 | 4 | 1.9 | 0.102 | 4 | 1.1 | 0.339 | 4 | 1.2 | 0.331 | ||||
| Error | 674 | 674 | 500 | 500 | ||||||||||||
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.