Ecosystem-Scale Effects of Nutrients and Fishing on Coral Reefs

Table 2

Models of effects of fishing on fish trophic group and size-class biomass.

Dependent	Predictor	AICc	ΔAICc^†	𝑤𝑖
Trophic-based Models
ln(Top Predators)	ln(Fish Catch)	93.67	0	99.8
	Fish Catch*	106.05	12.38	0.2
ln(Herbivores)	ln(Fish Catch)	113.73	130.52	≪0.1
Herbivores	Fish Catch	−16.79	0	100.0
Herbivores	Top Predators*	−0.86	12.64	0.2
	Quadratic Top Predators	−6.75	6.75	3.3
	Piecewise Top Predators^‡	−12.88	0	96.5
Size-based Models
ln(Large-bodied fishes)	ln(Fish Catch)	98.48	0	82.5
	Fish Catch	101.58	3.1	17.5
ln(Small-bodied fishes)	ln(Fish Catch)*	99.93	3.92	12.3
	Fish Catch	96.01	0	87.7
ln(Small-bodied fishes)	Large-bodied fishes*	98.35	12.28	0.2
	Quadratic Large-bodied fishes*	92.09	6.02	4.69
	Piecewise Large-bodied fishes^‡	86.07	0	95.11

^†Difference in AIC_c between a given model, 𝑖, and the model with the minimum AIC_c.
*All predictors are random variables, and models were estimated using ordinary least squares. However, if residuals exhibited spatial autocorrelation, relationships were estimated using spatial simultaneous autoregressive linear models.
^‡A piecewise regression model is of the form 𝑦=𝑎+𝑏₁𝑥+𝑏₂𝑥_𝑐, where 𝑎 is the intercept, 𝑏₁ and 𝑏₂ are slopes, and 𝑥_𝑐=𝑥−𝑐 (𝑐 is a cut point) if 𝑥≥𝑐 and 𝑥_𝑐=0 if 𝑥<𝑐.