![]() Even if this is true, the morphology, health, and functionality of these systems has declined substantially with ditching (which changed sinuous drainages into an angular grid), declining water quality, and changes in tidal hydrodynamics. It is possible that the number and acreage of this community may have increased in recent decades as mosquito ditches were cut into low salt marshes. ![]() Saltwater tidal creeks, which drain these marshes, may have suffered equally drastic declines, particularly from direct dredging and filling for urban development. Over the last several decades, there have been significant decreases in the area of extent, number, and ecological integrity of low salt marshes in New York. The primary threats to the community are shoreline development, marsh ditching, channel dredging and filling, declining water quality, diking and impoundment, changes to tidal hydrodynamics, and invasive species. The current trend of the community is thought to be declining. The community is restricted to salt marsh complexes along the seacoast in the Coastal Lowlands ecozone and along Long Island Sound in the Manhattan Hills ecozone. The several documented occurrences have good viability and are protected on public or private conservation land. There are estimated to be about 60 occurrences statewide. Some factors beyond salinity influencing the distribution of fish in tidal creeks include availability of food and presence of predators. ![]() ![]() Some species of fish are able to tolerate low, mid, and high salinity areas. Fish that spend most their time in the lower salinity areas of brackish or freshwater tidal creeks migrate farther upstream when the tides come in to avoid a sudden increase in salinity level. Fish that typically live in high salinity areas migrate into saltwater tidal creeks with high tide, following the increasing salinity level. Different species of fish are specialized for different levels of salinity. Changes in salinity and temperature can influence migration patterns of fish within tidal creeks. ![]()
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