The Israeli Journal of Aquaculture – Bamidgeh 56(1), 2004, 59-67.
EFFECTS OF LAND-BASED TROUT FARMS ON THE BENTHIC
MACROINVERTEBRATE COMMUNITY IN A TURKISH BROOK
Mine Uzbilek Kirkagac*, Serap Pulatsu, Gulten Koksal*
Department of Aquaculture and Fisheries, Faculty of Agriculture, Ankara University,
06110 Diskapi, Ankara, Turkey
(Received 20.7.03, Accepted 3.11.03)
Key words: benthic macroinvertebrate, diversity indices, fish farm effluents,
rainbow trout (Oncorhynchus mykiss)
Benthic macroinvertebrates and physico-chemical parameters were surveyed at the source of the
Karasu Brook in Bozuyuk, Bilecik Province, Turkey, and at the inlets and outlets of five rainbow
trout farms that use the brook water and discharge effluents into it. The dissolved oxygen, pH,
ammonia-nitrogen, nitrite-nitrogen, nitrate-nitrogen and total phosphorus in the farm effluents
were within effluent standards for trout farming in different countries. The macroinvertebrate
community in the brook consisted of Mollusca, Gastropoda (Physidae, Limnaedae, Planorbidae,
Neritidae), Bivalvia (Spharidae), Annelidae, Oligochaeta (Tubificidae), Hirudinea (Glossiphonidae,
Erpobdellidae), Arthropoda, Insecta (Chironomidae, Ephemerellidae) and Crustacea
(Gammaridae, Asellidae). Tubificidae and Chironomidae were generally observed in all sampling
stations; the highest abundance was in the inlets and outlets of the two farms nearest the source.
The most common measures of biodiversity, i.e., richness, Simpson’s index, Shannon-Wiener
index and evenness, were used during the year-long study.
* Corresponding author. Tel.: +90-312-3170550/1109, fax: +90-312-3185298,