Botryllus

A Intermediate genera from the “Other: Chordata” group, mostly found in Cobbles

Cobbles

Intermediate

Other: Chordata

Genera Characteristics Recorded Traits Possible Values
Size in cm
  • 11-20 cm
  • <1 cm
  • 1-10 cm
  • 11-20 cm
  • >20 cm
Genera Characteristics Recorded Traits Possible Values
Motility (Adult)
  • Sedentary (Estimated)
  • Adult
  • Short Range Mobility
  • Sedentary

“Sedentary” (estimated)

Motility (Larval)
  • Short Term Planktonic
  • Long Term Planktonic
  • Short Term Planktonic
  • Brooded or Laid Eggs

“Short Term Planktonic”

Lifespan
  • 1-2 years
  • >10 years
  • 3-10 years
  • 1-2 years
  • <1 year
Maturity
  • <1 year
  • >4 years
  • 3-4 years
  • 1-2 years
  • <1 year
Fecundity
  • 1 - 10
  • 1 - 10
  • 10 - 100
  • 100 - 1000
  • 1000 - 10000
  • 10000 - 1 million
  • > 1 million

Image: Botryllus © John Ryland

Vulnerability

Botryllus is an epifaunal and colonial sea squirt with a cushion-like growth form on bedrocks, boulders and cobbles. This genus is widely distributed in a diverse range of environments from the eulittoral to the upper circalittoral zone. Botryllus is a passive suspension feeder of suspended particulate matter. Vulnerability to dredging disturbance is likely to be high because of its fragile body and habitat.

Recoverability

Botryllus life span is one year, the reproduction age is reached earlier and up to 8 eggs are produced per zooid. This fast growing fouling organism may spread easily and the genus is self fertile; after fertilization and development a tadpole larvae is released. The larvae is free swimming, for up to 36 hours, with a dispersal potential between 1-10 km. This suggests that recovery after disturbance may be fast, provided that the substratum remains rich in coarser sediments such cobbles and boulders.

References

  • Biology

    • Chadwick-Furman & Weissman, 1995
  • Distribution

    • Hayward & Ryland, 1990
  • Reproduction

    • Chadwick-Furman & Weissman, 1995
    • Eckert, 2003