Hatchery Methods and Early Development of Gracilaria parvispora

	Moore, D.1, K. Fitzsimmons1, H. Borgeas1, M. Akutagawa2 and E. Glenn1

	1University of Arizona
	Environmental Research Laboratory
	2601 E. Airport Dr.
	Tucson, AZ 85706

	2Ke Kua'aina Hanauna Hou
	Star Route 265
	Kaunakakai, Moloka'i, HI  96748

	ABSTRACT

Gracilaria parvispora is an economically important seaweed in Hawaii.  Fresh G. parvispora is consumed directly and used in Hawaiian and several Oriental cuisines.  Due to chronic over-harvesting the supply of fresh product in the Hawaiian market has decreased precipitously and prices have increased.  To bring supplies back to the market, aquaculture of G. parvispora has been developed.  Initial studies were devoted to vegetative production by collecting plants from the wild for basket and tank culture.  Development of hatchery methods for production of sporeling plants is a more efficient method of increasing production.

Trials were conducted to induce release of cystocarps and determine settling success on various substrates.  Additional trials were conducted to quantify growth rates of sporeling plants.  A photomicrographic record was constructed of the early development of G. parvispora.  Spore settling was successful on a variety of substrates with densities of 28.9 + 4.2 spores per mm2.  The number of spores surviving and developing into juvenile plants after six weeks was greatest on multi-strand plastic line, and least on cotton rope, with plastic coated wire, cleaned stones, coral chips and polypropylene being intermediate.







Insert photo of mature thalli on line.







A prototype hatchery/nursery system was developed utilizing filtered seawater and tanks for induction of spore release from parent plants and spore settling on substrate materials.  Additional tanks are used for early growth of the sporeling plants before stocking into ponds for growout.