Mangrove cover effect on Anadara tuberculosa: exploratory study in Puerto Jelí, Ecuador.

Mangroves provide critical habitat for Anadara tuberculosa, but environmental factors influencing morphometry are poorly understood. AUSCEM agreements require baseline knowledge about habitat-species relationships. This study explored relationships between tree canopy cover, substrate inclination, and A. tuberculosa morphometry in Puerto Jelí, Ecuador.  We sampled 510 individuals across 15 sites with 45 1m² quadrats. Linear mixed models evaluated effects of environmental variables on body length of non-commercial individuals (<45 mm, n = 409).  Tree canopy cover showed a statistically significant (p <0.05) but small effect on body length (marginal R² = 0.017, conditional R² = 0.089).  The model explained <2-10 % of total variance. Substrate inclination was not significant. Although statistically detectable, the canopy cover effect is biologically small, but typical for ecological data. Other unmeasured factors (temperature, granulometry, organic matter) likely have greater influence. Multivariate research is required to develop robust habitat quality indicators.