Resource partitioning by Menidia menidia and Menidia beryllina (Osteichthyes: Atherinidae)

Abstract

Resource overlap values were calculated for habitat and food utilization by Menidia menidia and M. beryllina in 2 Rhode Island estuaries (USA). Habitat overlap was nearly complete during spring, but declined during summer and fall. Food overlap varied greatly throughout the year. The 2 species coexist because they: (a) overlap strongly in both food and habitat utilization only when food is abundant, and (b) have evolved different spawning times and different growth rates. M. menidia grows to a larger body size than M. beryllina and can utilize different habitats and foods when zoopla.nkton becomes scarce. Time of hatching of each species in the upper estuary was related to cycles of zooplankton abundance M. menidia larvae probably have a substantial predatory impact on zooplankton In the upper estuary during June of each year.

The record of daily growth in otoliths of Atlantic silversides, Menidia menidia, from field and laboratory

“…The fact that actual growth declined abruptly in weeks 9 and 10 of 1977 coincides with the observation that growth of M . menidia, as measured by length-frequency diagrams, also slows in late summer (Bengtson, 1984).…”

Seasonally varying importance of abiotic and biotic factors in marsh-pond fish communities

“…Fundulus heteroclitus can consume a wide range of food items (Fritz 1974, Baker-Dittus 1978, Kneib & Stiven 1978, Kneib et al 1980, Kneib 1986, whereas Membras martinica are primarily zooplanktivorous (Bengston 1984, Morgan 1990, Allen et al 1995. Thus, direct food competition between these 2 species would not be expected.…”

Correspondence between environmental gradients and summer littoral fish assemblages in low salinity reaches of the Chesapeake Bay, USA

“…There appears to be no species specialized for exclusive existence in tidal freshwater reaches of the lower Chesapeake Bay, though the inland silverside is largely constrained to these environs, probably due to the presence of the Atlantic silverside within the estuary (Bengtson 1984). Dominant members of the freshwater fauna were cosn~opolitan in distribution, particularly the adult cyprinnids, and several sub-dominant but common species served as indicators for particular substrate types.…”