BIOLOGY One of three principal species found in British waters, razor clams are bivalve molluscs found in intertidal waters. Spawning occurs in summer. Fertilised eggs develop into mobile larvae hours after fertilisation. The larval phase includes several stages and lasts for about 3-4 weeks, during which time they drift with the current. The larval phase ends when larvae settle, attaching themselves to sand or shell by byssal threads. At around 5 mm length juveniles burrow into sand. They are long-lived and may survive to 16-18 years. ADVICE Avoid eating clams dredged from wild stocks. Choose clams harvested in the wild by sustainable methods only (such as hand-gathering). Avoid eating undersized animals (less than 10mm) and wild clams harvested during the spawning season (May - September).
BIOLOGY A bivalve mollusc with distinctive black and white shell markings, it is native to the waters of east Asia. Now widespread throughout the western world, with introductions made accidentally with oysters into North America, and deliberately as hatchery broodstock into Europe. In the wild it is found burrowing on coarse sediment in intertidal waters. Matures at about 2 years, with a corresponding shell size of about 20 mm. Maximum size about 65-75 mm. Spawning occurs in summer months. ADVICE All Manila clams in the UK are progeny of broodstock imported from the west coast of USA. They are grown in trays on trestles in the sea before planting out in ground plots or seabed. Only a small number of manila clams are farmed for the table in UK (6 tonnes, 2004), the biggest production is seed for ongrowing. Clams may be harvested by manual digging or raking, or by mechanical methods e.g. suction or hydraulic dredge. Manual harvesting methods cause less disturbance to sediment than mechanical methods. Shellfish farming is an extensive, low-impact method of mariculture and high quality water standards are required for cultivation of shellfish for human consumption. When buying any farmed fish, including shellfish, ask your fish supplier if they have a buying policy that ensures high environmental farming standards are required.
BIOLOGY Clams are bivalve molluscs found world-wide in temperate waters on both sides of the Atlantic. A number of different species may be marketed as clams, including species introduced from other areas of the world e.g.Manila clam and American hard shell clam. Clams can be farmed or harvested from wild stocks.
GELOMBANG DAPAT TERJADI 1,0 M S/D 2.0 M DI : PERAIRAN SABANG, PERAIRAN ACEH, PERAIRAN BARAT PULAU NIAS, PERAIRAN KEP. MENTAWAI, SAMUDERA HINDIA BARAT BENGKULU HINGGA LAMPUNG SELATAN, PERAIRAN ENGGANO, SELATA SUNDA BAG. SELATAN, SAMUDERA HINDIA SELATAN JAWA, PERAIRAN PULAU ROTE, LAUT TIMOR, PERAIRAN KEP. DAMAR DAN TANIMBAR, LAUT SULAWESI BAG. TIMUR, PERAIRAN KEP. SANGIHE, LAUT HALMAHERA BAG. TIMUR, PERAIRAN UTARA KEPALA BURUNG, LAUT ARU BAG. SELATAN, PERAIRAN BARAT LAUT PULAU YOS SUDARSO DAN PERAIRAN BARAT MERAUKE ( YANG BERBAHAYA BAGI PERAHU NELAYAN DAN TONGKANG ) GELOMBANG DAPAT TERJADI 2.0 M S/D 3,0 M DI : SAMUDERA HINDIA UTARA HINGGA SELATAN ACEH, PERAIRAN BANTEN, LAUT ARAFURA BAG. UTARA DAN PERAIRAN SELATAN PULAU YOS SUDARSO. ( YANG BERBAHAYA BAGI PERAHU NELAYAN ,TONGKANG, TUGBOAT, RORO, LCT DAN FERRY ) REKOMENDASI ( PERINGATAN DINI ) GELOMBANG DAPAT TERJADI 3,0 M S/D 5.0 M DI : LAUT ANDAMAN DAN LAUT ARAFURA BAG. SELATAN.( YANG BERBAHAYA BAGI SEMUA JENIS KAPAL) ADANYA AWAN GELAP (CUMULONIMBUS) DI LOKASI TERSEBUT DAPAT MENIMBULKAN ANGIN KENCANG DAN MENAMBAH TINGGI GELOMBANG SUMBER : DEPARTEMEN KELAUTAN DAN PERIKANAN