Experimental set-up required a total of 5 days, with each block requiring
one day for deployment. A 0.25 m2 square quadrat was placed
over the substrate, rocks were moved to a large bin, and all
H. sanguineus in the quadrat were removed. The top 5 cm of sediment
within the quadrat was also removed and placed into another bin. The
cagewas fitted into the quadrat, excavated sediment and rocks were replaced
inside the cage, and the outside of the cagewas secured to metal
rods embedded in the substrate. The area around the cagewas returned
as close as possible to the original condition. Each treatmentwas spaced
1 m from the adjacent treatment. Once all the cages had been buried
into the ground, the tops were closed with cable ties. The 0.25 m2 open plot was staked and the rocks and sediment in the plot were
disturbed similarly to the other treatments.