Table 1.

AICc 95% confidence set of models relating female body length, migration difficulty, age, and river discharge–length interaction to (A) egg mass, (B) fecundity, (C) gonad mass, and (D) the ratio of egg number to egg mass

	Reproductive trait	Model	k	log Lik	AICc	ΔAICc	wi
(A)	Wet egg mass	Discharge + Length	7	−4486.9	8988	0.00	0.70
	Wet egg mass	Age + Discharge + Length	8	−4486.8	8990	1.85	0.28
(B)	Fecundity	Age + Length	7	−9110.1	18234	0.00	0.36
	Fecundity	Length	6	−9111.3	18235	0.19	0.32
	Fecundity	Discharge + Length	7	−9110.8	18236	1.48	0.17
(C)	Gonad mass	Discharge + Length	7	−6369.5	12753	0.00	0.57
	Gonad mass	Age + Discharge + Length	8	−6369.5	12755	1.90	0.22
	Gonad mass	Length	6	−6371.9	12756	2.66	0.15
	Gonad mass	Age + Length	7	−6371.9	12758	4.67	0.06
(D)	Number:size	Discharge + Length	7	−4289.8	8594	0.00	0.55
	Number:size	Age + Discharge + Length	8	−4289.4	8595	1.16	0.31
	Number:size	Length	6	−4292.8	8598	3.84	0.08
	Number:size	Age + Length	7	−4292.1	8598	4.45	0.06

ΔAICc is the difference in AICc values between model i and the best model of those considered, and w_i is the probability that a model is the best model of the set. All models included population identity as a fixed factor and a random intercept by year.