Table 3. Results of covariance analysis corresponding to the linear regressions drawn in Figure 2 C and D.

Species	Intercept Slope	Winter	Spring	Autumn	Summer
Donax trunculus	Winter
	Spring	0.0004 *		<0.0001*
	Autumn	<0.0001 *	0.24
	Summer	<0.0001 *	0.003 *	0.002 *
Donax semistriatus	Winter		0.16	<0.0001*
	Spring	0.71		<0.0001*
	Autumn	0.64	0.9
	Summer	0.003 *	0.0001 *	<0.0001 *

P-values are indicated for the comparison between slopes and intercepts for each season and species.

^*: statistically significant.