Finally, M. latisulcatus did not distinguish between seagrass, artificial seagrass or epiphytised artificial seagrass, although they did avoid artificial seagrass and sand when sand alone was present, suggesting that artificial seagrass may have hindered burying.
Epiphytised and clean artificial seagrass elicited identical responses, indicating that the extra structure and potential food source offered by epiphytes had no effect on the habitat chosen.
While epiphyte composition was not quantified, it consisted of turfing algae, crustose coralline algae, Ulva, and sessile and mobile invertebrates including bryozoans, sponges, ascidians, polychaetes and amphipods, as well as some sediment and detritus.
Thus, epiphytised artificial seagrass would have provided both greater habitat complexity and at least a minor source of food.
Bologna and Heck (1999a) found that the presence of epiphytes on artificial seagrass increased the abundance of mobile epifauna, as they provided a source of food.
As the epiphytised artificial seagrass had been in the ocean for 6 months prior to use, the lack of selection between it and new clean artificial seagrass suggests that lack of preference for the latter in sand vs. artificial seagrass trials was not due to avoidance of chemicals leaching from the plastic.
This conclusion is further supported by the lack of selection between artificial seagrass and live Zostera, which validated our decision to use the former for most trials.
Each tria with real seagrass required about as much time to set up and then search at completion, as did all six trials employing combinations of other habitats, and thus use of artificia seagrass resulted in considerable savings in time.