Ecology

Figure 6: Environment in which B. leachi was found in on Heron island. 

Table 1: Habitats of B. leachi. Adapted from NIMPIS 2012b. 

B. leachi is more prominent in the summer months as the colonies are at their biggest and more conspicuous (Newton et al., 2007). B. leachi is also more commonly found in sheltered areas than at exposed sites (Newton et al., 2007). 

A study conducted by on B. leachi in the Venetian lagoon discovered that colonies enter a condition called winter quiescence (Burighel et al., 1976, Coma et al., 2000). This happens during winter when the temperature is less than 10°C (Coma et al., 2000). The condition is characterised by a reduced number of functional filtering zooids, a decreased rate of budding and a reduction in sensitivity to mechanical stimuli (Burighel et al., 1976, Coma et al., 2000). 

Associations

Interspecific associations are relationships that B. leachi have with other species. 

Ascidians are not subjected to much predation (Epelbaum et al., 2009, Stoecker, 1980). However, nudibranchs, snails, slugs (phylum: Mollusca, class: Gastropoda) (NIMPIS, 2012a, Stoecker, 1980), and flatworms (phylum: Platyhelminthes) have been known to feed on B. leachi (Epelbaum et al., 2009, NIMPIS, 2012a). Skeleton shrimps (Caprella spp) are also known to anchor and feed on micro-algae and detritus that accumulate on the surface of the colony (Epelbaum et al., 2009). 

Ectoparasites, Botryllophilus rubber Hesse, 1864, Mychophilus reseus Hesse, 1866 and Mychophilus rosovula Gray, 1933 are the only parasites that have known associations with B. leachi (Gotto, 1954, Gotto, 1966). The effect of the association these parasites have with B. leachi is still unknown.