Effects of pile size of artificial reefs on the standing stocks of fishes

Abstract

The relationship between production and reef pile size was analysed using standing stocks of fishes surveyed at three established artificial reef (AR) habitats in the subtropical waters off the northern coast of Taiwan during April-August 1999. For a closer look, the fish assemblage was further divided into visitors and residents, and biomass was used as a parameter to represent production. Visitors were characterised by sporadic occurrences and highly variable school sizes. However, large schools (containing more than 200 kg of biomass) occurred only around small AR piles (consisting of less than 15 units of 2-m 3 concrete reef). Considering visitors alone, the correlation between biomass and pile size was not significant for the combined data from three sites. Changes in the standing stock of residents followed a clearer trend, and the relationship could be fitted to a sigmoidal equation. This trend shows that collections of the residents tended to increase until the pile reached a size of 20-30 reef units. Thereafter, the increase in biomass slowed, and maximum biomass would eventually be reached only with a further increase in the pile size. Predictions of the efficiency of unit reefs for different pile sizes indicate that a pile consisting of 4-10 units of this type of reef would be most effective in terms of biomass of residents. Nevertheless, a size of 15 units is recommended when the behaviour of visitors is taken into account.

Ecological effects of artificial reefs in Daya Bay of China observed from satellite and in situ measurements

“…6 and 7). Additional surface area with increased reef pile size helps attain the maximum fish biomass (Jan et al, 2003). Considering that the natural habitat has disappeared in Daya Bay (Jia and Zhuang, 2009;Wang et al, 2010), ARs can provide a suitable habitat and spawning ground for larval and juvenile fish (Figs.…”

Distinguishing resident from transient species along marine artificial reefs

“…Marine artificial reef studies commonly refer to the distinction between resident and non-resident species (e.g. D'Anna et al , 1994; Johnson et al , 1994; Moreno, 2002; Jan et al , 2003). Beyond traditional community monitoring, the core species-transient species distinction appears essential to performance assessment of these objects generally deployed either for fishery purposes or environmental mitigation (Ambrose, 1994; Caselle et al , 2002).…”

Simulation‐based investigations of fishery changes as affected by the scale and design of artificial habitats

“…The reef consists of two types of reef blocks and two sizes of reef module allowing issues of scale and habitat complexity to be studied in relation to colonization and habitat utilization by commercially viable species. Such issues are important in assessing optimal designs for artificial habitats for enhancing fish stocks (Jan et al ., 2003). A research and monitoring programme has been underway at the LLAR site since 1998, involving hydrographic, epifaunal, infaunal and broad‐scale mapping studies (Sayer & Wilding, 2002; Wilding & Sayer, 2002 a , b ; Wilding et al ., 2003; Collier & Brown, 2005).…”