Reproductive cycle of the bivalves Ensis macha (Molina, 1782) (Solenidae), Tagelus dombeii (Lamarck, 1818) (Solecurtidae), and Mulinia edulis (King, 1831) (Mactridae) in southern Chile

The reproductive cycles of the bivalves Ensis macha (Molina, 1782), Tagelus dombeii (Lamarck, 1818), and Mulinia edulis (King, 183 1) were studied at six sites in southern Chile (38-43degreesS) from November 1996 to December 1997. Samples of E. macha came from three subtidal shallow depths; those of T. dombeii from two subtidal depths and one intertidal site; and samples of M. edulis originated in one subtidal shallow depth and one intertidal site. Thirty specimens were collected monthly for standard histological analyses. Water samples were also collected to determine salinity, temperature, and chlorophyll a content. In general, the reproductive cycles of the three species were characterized by long spawning periods, beginning during late spring-summer. In some cases, that period extended during autumn-winter until the following spring. The gonads of most of the populations showed quite short recovery periods, with the exception of populations located farther south, which needed more time to begin a new cycle. Comparison of subtidal versus intertidal populations showed that the gonad stages developed more slowly for the latter populations. The earlier results show that variability exists in the timing of gametogenic cycles of E. macha, T. dombeii, and M. edulis along the coast of southern Chile. No significant relationship was found between seasonal variability of reproductive stages and seasonal variability of water characteristics. Among these characteristics, water temperature and chlorophyll a content were the most important. Potential fecundity varied geographically in E. macha and T. dombeii, whereas, in general, no variability was observed in mean sizes of oocytes of the three species. These results must be taken into account when management plans are designed; thus, the timing of the gametogenic cycles of bivalves of economic importance must be studied along their full geographic ranges.PT: J; CR: ARACENA O, 1998, 17 C CIENC MAR IQ CH ARRATIA L, 1998, THESIS U AUSTRAL CHI BANCROFT J, 1977, THEORY PRACTICE HIST BARBER BJ, 1981, J EXPT MARINE BIOL E, V52, P121 BAYNE BL, 1983, MOLLUSCA, V4, P491 BORRERO FJ, 1987, BIOL BULL, V173, P160 BRATTSTROM H, 1983, SARSIA, V68, P289 BROUSSEAU DJ, 1995, J SHELLFISH RES, V14, P483 CLASING E, 1998, ALIMENTACION SUSPENS DAY RW, 1989, ECOL MONOGR, V59, P430 DEFEO O, 1987, BIOL PESQUERA, V16, P47 DEFEO O, 1989, FISHBYTE, V7, P25 DEFEO O, 1993, BIOL PESQUERA, V22, P41 EVERSOLE AG, 1980, P NATL SHELLFISH ASS, V70, P22 FIERRO J, 1981, THESIS U CONCEPCION FUENTES I, 1988, THESIS U CATOLLICA N GALLARDO C, 1996, BIOL PESQUERA CHILE, V25, P41 GARCIADOMINGUEZ F, 1996, J SHELLFISH RES, V15, P297 GIESE A, 1977, REPROD MARINE INVERT, P1 GRIFFITHS RJ, 1981, ESTUAR COAST SHELF S, V13, P477 HARVEY JW, 1991, COMP HAEMATOL INT, V1, P55 HARVEY M, 1989, J EXP MAR BIOL ECOL, V129, P199 HARVEY M, 1993, MAR BIOL, V115, P421 HEFFERNAN PB, 1989, J SHELLFISH RES, V8, P327 HEFFERNAN PB, 1989, J SHELLFISH RES, V8, P51 HEFFERNAN PB, 1989, J SHELLFISH RES, V8, P61 JARAMILLO E, 1995, J SHELLFISH RES, V14, P253 JARAMILLO E, 1998, 9646 FIP KANTI A, 1993, J SHELLFISH RES, V12, P255 LAASUY DR, 1989, 82 US FISH WILDL SER LANDERS W, 1954, US FISH WILDLIFE SER, V117, P1 LASEN J, 1979, SEM TIT U CHIL CHIL LEPENNEC M, 1991, J EXPT MARINE BIOL E, V142, P151 LOOSANOFF VL, BIOL B, V82, P195 LOZADA E, 1989, REV PACIFICO SUR, P355 MACDONALD BA, 1985, MAR ECOL-PROG SER, V25, P295 MACKIE GL, 1984, MOLLUSCA, V7, P351 MANZI JJ, 1985, VELIGER, V28, P186 MASELLO A, 1987, THESIS U REPUBLICA U MCLACHLAN A, 1974, ZOOL AFR, V9, P15 NEUER H, 1966, ZEISS INFORMATION OSORIO C, 1979, BIOL PESQ CHILE, V11, P3 PAREDES A, 1986, BIOTA, V1, P32 PEREDO S, 1987, VELIGER, V30, P55 RICHARDSON CA, 1993, J SHELLFISH RES, V12, P207 ROPES JW, 1968, BIOL BULL, V135, P349 SANTOSSALAS CM, 1998, 18 C CIENC MAR IQ CH SASTRY A, 1979, BIOL BULL, V140, P274 SASTRY AN, 1979, REPRODUCTION MARINE, V5, P113 SERNAPESCA, 1997, ANUARIO ESTADISTICO SOKAL R, 1995, BIOMETRY PRINCIPLES STRICKLAND J, 1972, FISHERIES RES BOARD, V167 STRUB P, 1998, SEA, P273 TARIFENO E, 1980, THESIS U CALIFORNIA URBAN HJ, 1994, MAR ECOL-PROG SER, V115, P93 VILLALEJOFUERTE M, 1995, VELIGER, V38, P126 VILLALEJOFUERTE M, 1996, B CIENTIFICO SANTA F, V4, P29 VILLALEJOFUERTE M, 1996, J SHELLFISH RES, V15, P741 VIVIANI CA, 1979, STUD NEOTROP FAUNA E, V14, P65 WALKER RL, 1994, J SHELLFISH RES, V13, P479 WEIBEL ER, 1969, INT REV CYTOL, V26, P235; NR: 61; TC: 3; J9: VELIGER; PG: 12; GA: 508XYSource type: Electronic(1