Table 3.
Tweedie GLM to predict shark abundance on BRUVS
| Factors | Degrees of freedom (DF) | Deviance | Residual DF | Residual deviance | F-value | p value | Deviance explained |
|---|---|---|---|---|---|---|---|
| Null | 66 | 47.61 | |||||
| log10(Gravity) | 1 | 12.47 | 65 | 35.14 | 4.49 | <0.0001 | 0.26 |
| Protection status | 1 | 0.01 | 64 | 35.12 | 2.88 | 0.87 | 0.0003 |
| Reef complexity | 1 | 3.68 | 63 | 31.45 | 28.26 | 0.01 | 0.08 |
| Protection status ∗ log10(Gravity) | 1 | 0.29 | 62 | 31.16 | 0.64 | 0.43 | 0.01 |
| Sum of deviance explained | 0.35 | ||||||
Analysis of deviance table of Tweedie GLM to determine the effects of key anthropogenic (protection status [open or closed to fishing], log-transformed market gravity score) and habitat (mean reef complexity score [0–5]) factors on the reef-level occurrence (mean MaxN) of sharks on reefs throughout the greater Caribbean (n = 67 reefs). An asterisk denotes the interaction between factors.