Relative growth and reproductive cycle of the date mussel Lithophaga lithophaga (Linnaeus, 1758) sampled from the Bizerte Bay (Northern Tunisia)

Table 1 Relationships between biometric variables of Lithophaga lithophaga from the Bay of Bizerte (sexes combined)

Biometric variables	Period	N	y = bx ^a log y = a log x + log b	t	P	Type of growth
W on L	Annual	975	0.294x ^0.9918 r = 0.96	3.337	<0.001	−
	Autumn	292	0.2617x ^1.021 r = 0.97	4.666	<0.001	+
	Winter	181	0.3863x ^0.9272 r = 0.95	11.841	<0.001	−
	Spring	240	0.3133x ^0.9771 r = 0.96	4.693	<0.001	−
	Summer	262	0.2623x ^1.0173 r = 0.97	918.493	<0.001	+
H on L	Annual	975	0.1566x ^1.1148 r = 0.96	43.157	<0.001	+
	Autumn	292	0.1223x ^1.1765 r = 0.96	36.23	<0.001	+
	Winter	181	0.2436x ^1.0096 r = 0.95	1.581	n.s.	=
	Spring	240	0.1852x ^1.0747 r = 0.96	14.154	<0.001	+
	Summer	262	0.1279x ^1.1611 r = 0.96	32.857	<0.001	+
S d. w. on L	Annual	975	log y = 2.613 log x − 4.122 r = 0.95	14.786	<0.001	−
	Autumn	292	log y = 2.597 log x − 4.116 r = 0.96	9.176	<0.001	−
	Winter	181	log y = 2.628 log x − 4.142 r = 0.97	7.536	<0.001	−
	Spring	240	log y = 2.746 log x − 4.332 r = 0.94	4.105	<0.001	−
	Summer	262	log y = 2.500 log x − 3.924 r = 0.95	9.786	<0.001	−
ST d. w. on L	Annual	975	log y = 2.611 log x − 4.780 r = 0.9	9.498	<0.001	−
	Autumn	292	log y = 2.092 log x − 3.981 r = 0.92	17.212	<0.001	−
	Winter	181	log y = 3.126 log x − 5.689 r = 0.93	1.335	n.s.	=
	Spring	240	log y = 2.782 log x − 5.001 r = 0.94	3.250	<0.05	−
	Summer	262	log y = 2.758 log x − 4.969 r = 0.91	3.17	<0.05	−
T w. w. on L	Annual	975	log y = 2.584 log x − 3.653 r = 0.95	14.884	<0.001	−
	Autumn	292	log y = 2.763 log x − 4.058 r = 0.97	5.532	<0.001	−
	Winter	181	log y = 2.576 log x − 3.566 r = 0.97	9.414	<0.001	−
	Spring	240	log y = 2.527 log x − 3.469 r = 0.97	11.084	<0.001	−
	Summer	262	log y = 2.524 log x − 3.574 r = 0.96	11.116	<0.001	−

L shell length, W shell width, H shell height, S d. w. shell dry weight, ST d.w. soft tissues dry weight, T w.w. total dry weight, N number of N number of individuals, n.s. statistically not significant
Positive allometry (+), negative allometry (-), isometry (=)

ISSN: 1438-3888