Salt+Marsh

Brad Brooks and Sam Dever

Salt Marsh

1) Salt Marshes are found along the eastern coast of the United States, in New Zealand, along rivers in the Mississippi Delta (United States) and in southern Europe.

2) Salt Marshes are transitional areas between land and water, with wide ranges of temperature, salinity, and depth. They are very heavily influenced by tides, and occur in the zone between high and low tides. Salt marshes cannot thrive where waves are strong, but tend to survive better when waves are smaller and less powerful. They are made up of numerous green, brown, and gray colored plants, and have a very high marine species biodiversity.

3) a) Native species in the salt marsh include: fiddler crabs, marsh snails, marsh mussels, insects, fishes, crabs, shrimps, blue crabs, white shrimp, spot tail bass, mummichogs, grass shrimp, diamond back terrapins, American alligators, red-winged black birds, herons, and egrets.

b) One of the more prolific nonnative species in the salt marsh is the phargmites, which is a type large grass that is found in wetlands. This aggressive reed grass has invaded many of the marshes on the eastern coast of the United States. It can reduce the number of native fish and wildlife populations that would normally be there. Phargmites out grow and take the place of natural vegetation in the salt marsh, which is bad because phargmites provide little or no food and shelter for the wildlife. Also phargmites can cover up small intertidal channels that is a refuge and feeding ground for fish, invertebrates, and waterbirds.

c) Indicator species include many different plants (including: Araneae, Rhynchota, Coleoptera and selected families of Diptera) and salt marshes are especially dominated by smooth cordgrass, which is a major indicator species within the salt marsh ecosystem. Smooth cordgrass is unique in its ability to withstand varying salt concentrations and high temperatures due to its special salt secreting glands. Since few animals eat this species, it stays alive and productive and therefore can indicate a varying salinity or heat change dpeneding on its growth or death within a specific marsh.

d) The Harvest mouse is a keystone species of the salt marsh environment. Pictured on the right, the harvest mouse is most noted because of its ability to move seeds about throughout the environment and disperse them within their habitat. It is important to the salt marsh environment because it has a unique ability to drink salt water for extended periods of time if it needs to, and can tolerate varying amounts of salt content, and is a fairly good swimmer. Its diet consists mainly of the main plants found in salt marshes, making it easy for the species to thrive.

e) Stickleback fish often occur in salt marshes with other fish species, such as killifish and silversides. Even though these species have similar diets, they have learned to feed at different times and broaden the range of their diet so that they do not deal with as many effects of interspecific competition. This species is also very important to the salt marsh ecosystem.

f) A type of bird called a heron is a major predator in the salt marsh. They have long legs that they use to walk through the water in search of fish to eat. They normally sit and wait in a shallow region for their prey to come close enouph to strike.

g) Mangrove trees and the sponges Tedania ignis and Haliclonia implexiformis are great examples of a mutuality relationship. The mangrove tree has roots that are partly above ground, the sponges attach themselves to the roots. When the sponge hooks onto the roots the sponge gives the tree nitrogen and the tree gives the sponge carbon.

4) [|Current Event] This current even article is from May 10th, 2007. It describes the lasting effects of the 1969 oil spill that continues to effect the salt marsh known as Wild Harbor, located on Cape Cod. One of its main lasting effects is with fiddling crab burrowing behaviors. It appears as though they are digging shorter, twisted burrows rather than longer, straight burrows. The longer burrows aerate the sediment that enhance growth of sea grass beds in the marsh. This provides a habitat and prevents erosion. It also describes how the oil spill still effects the feeding patterns and population growth of fiddler crabs, and how oil spill cleanup is very difficult.

5) Website Citations http://en.wikipedia.org/wiki/Salt_marsh http://des.nh.gov/organization/commissioner/pip/factsheets/cp/documents/cp-08.pdf http://www.dnr.sc.gov/marine/pub/seascience/dynamic.html http://upload.wikimedia.org/wikipedia/commons/9/97/Bride-Brook-Salt-Marsh-s.jpg http://www.conbio.org/resources/Tips/images/v18n2_mousecollarLG.jpg http://onlinelibrary.wiley.com/doi/10.1111/j.0022-0477.2004.00903.x/full http://pond.dnr.cornell.edu/nyfish/Gasterosteidae/threespine_stickleback.jpg http://des.nh.gov/organization/commissioner/pip/factsheets/cp/documents/cp-08.pdf