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R/V KATY Volunteer Training Manual UNIVERSITY OF TEXAS MARINE SCIENCE INSTITUTE MISSION ARANSAS NATIONAL ESTUARINE RESEARCH RESERVE 1 CONTENTS INTRODUCTION Background Information _______________________ 3 PROCEDURES Safety _______________________ 6 Trip Outline _______________________ 6 Trip Checklist _______________________ 7 Emergency Procedures _______________________ 10 Volunteer Job Description _______________________ 11 RESOURCES Contact Information _______________________ 11 Appendix _______________________ 12 2 INTRODUCTION Background Information The University of Texas Marine Science The central Texas coast has two major bay Institute is located at the north end of Mustang systems. The Aransas Bay System, north of Port Island. Across the ship channel to the north is San Aransas, covers an area of 157 square miles and Jose Island. These are two of a string of barrier islands includes Aransas, Copano, and Mission Bays. Aransas that form a protective ribbon of sand that stretches Bay is located behind San Jose Island. It’s maximum from south of Brownsville to north of Galveston, a depth is 5 to 6 feet deep in the north end of the bay distance of some 270 miles of open beach. Between increasing to 10 to 13 feet at the southern end near the mainland and the barrier islands lie shallow the Lydia Ann Channel. bays and lagoons that form a rich nursery ground One of the areas frequesntly visited on R/V teeming with marine life. KATY trips is located at the junction of the Lydia The soft bottoms of the bays are rich in Ann Channel and Aransas Bay. It represents a hard nutrients, supporting a diverse community of substrate environment. Otter trawl samples are molluscs, marine annelids, crustaceans, and benthic collected here in a long trough, averaging 24 to 28 algae. The margins of the bays and lagoons are feet deep, formed by the large volumes of water covered with dense seagrass meadows that provide funneling from Aransas Bay through the narrow Lydia both food and shelter for larval and juvenile forms Ann Channel. This massive water movement occurs of marine life. during hurricane storm surges and, more frequently, Sabine Pass Bolivar Peninsula Aransas Pass at Port Aransas Bolivar Pass Galveston Island San Luis Pass Sabine Pass Follets Island Matagorda Peninsula Pass Cavallo Matagorda Island Bolivar Pass Cedar Bayou San Jose Island Aransas Pass Mustang Island Packery Channel San Luis Pass Padre Island Mansfield Pass Pass Cavallo Brazos Santiago Pass Brazos Island Packery Channel Texas Gulf Facts Boca de Sandoval • The Texas Coast is approximately 375 miles • Southeast winds create longshore currents •long, from Sabine Pass to Brazos Santiago •which converge off North Padre Island. Pass. • Longshore currents move sand to this area, Boca de San Antonio • The Texas Coast is on the northwest portion of •south from Galveston and north from South Boca de Jesus Maria Mansfield Pass •the Gulf of Mexico. Padre Island. • The Texas mainland is protected by an almost • Padre Island is one of the longest barrier islands Map Graphic “From SHORE ECOLOGY OF THE GULF OF MEXICO • • by Joseph C. Britton and Brian Morton, Copyright (c) 1989. continuous string of sand barrier islands. in the world. By permission of the University of Texas Press.” • This arc-shaped coastline and the string • There are eight natural passes between the •of barrier islands were created by onshore •barrier islands that allow bay water to exchange Courtesy photographs by Richard L. Watson, Ph.D., P.G. winds, which blow out of the southeast for with Gulf of Mexico water. http://TexasCoast Geology.com Brazos Santiago Pass approximately nine months each year. This sign is located in the Wetlands Education Center and depicts the chain of barrier islands that make up the Texas Coast. 3 Introduction during passage of very windy cold fronts in the winter. Lighthouse), built in 1855, also is located on Harbor The moving water scours the bottom and carries Island. Its beacon guided sailors across San Jose Island finer sediments up the channel, leaving the heavier through the many natural passes that once existed shell and shell fragments behind. Some of the shell there. The present pass is a natural pass that has been fragments found there are slowly being destroyed by jettied with granite boulders and deepened to 45 feet the boring sponge, Clione sp. to allow ships to pass through the barrier island to the The shells in the Lydia Ann Channel also inshore ports. provide attachment points for a host of other marine invertebrates, such as encrusting bryozoan, star coral, serpulid worms, barnacles, oyster spat, ribbed mussels, and hydroids. The shell rubble is also home for several species of mud crabs, amphipods, brittle stars, snapping shrimp, and tunicsates, as well as a variety of gobies, blennies, and skillet fish. USCG Chart of the Corpus Christi Bay System. To the south of Port Aransas is the Corpus Christi Bay system, made up of Corpus Christi Bay, Nueces Bay, and Redfish Bay, an area of approximately 200 square miles. Corpus Christi Bay is the largest of the three with an area of 152 square miles. It has an average natural depth of 12 to 15 feet, grading up to a The Lydia Ann LIghthouse. depth of 3 to 5 feet along the margins of the bay. The The Lydia Ann Channel extends to the south sediment is dark, clay-like mud with scattered oyster between San Jose Island and Harbor Island. The reefs located in the shallows along the shore. remainder of the channel averages 12 to 15 feet deep Nueces Bay, one of the two true riverine- over a sandy-mud bottom. The Harbor Island area influenced estuaries along the central Texas coast, is on the west side of the channel is the largest black located on the northwest edge of Corpus Christi Bay. mangrove marsh in Texas. The shallow sloughs and Nueces Bay is a small, shallow bay covering an area lakes within the marsh provide shelter and food for of 29 square miles. Runoff from the Nueces River and the area. The marsh also is home to many of the larger its upstream drainage basin plays an important role wading birds, such as the Reddish Egret, Great Blue in nutrient cycling and regeneration throughout the Heron, Snowy Egret, Great Egret, and the Roseatte Corpus Christi Bay system. Dams placed upstream, Spoonbill. however, will reduce the flow of the river and affect The Aransas Pass Lighthouse (or Lydia Ann both the salinity gradient of the bay and the nutrient 4 Introduction flushing and cycling that occurs after periodic floods. marine life to move between the bay nursery grounds Redfish Bay is on the northeast side if Corpus and the shallow, productive continental shelf off Christi Bay. This small, shallow bay has an average the Texas coast. During virtually every month of the depth of only 3 to 8 feet and covers an area of 19 square year, some form of adult marine life - fish, shrimp or miles. The sediment varies from coarse shell along the crab- is migrating from the shallow bays and lagoons margin of the ship channel to soupy, claylike mud in through channels and barrier islands into the shallow the upper parts of the bay. Redfish Bay’s margins are Gulf shelf to spawn either offshore or in the mouth heavily vegetated with several species of seagrasses of the channel. The native Gulf white shrimp, Penaeus as well as dense growths of macroalgae. Stands of setiferus, is a typical example. submerged vegetation form dense meadows that After hatching from an egg, shrimp begin provide both food and shelter for a host of larval and life offshore as larvae. Being poor swimmers, they juvenile marine life. are carried by tides and currents through passes South of Corpus Christi Bay is a long, narrow into shallow bays and lagoons. As postlarvae, they body of water called the Laguna Madre. It extends take up residence in the rich nursery grounds. some 115 miles behind Padre Island south to Port Shrimp are omnivorous bottom feeders, and their Isabel. There is very little water movement in Laguna food consists of algae, molluscs, marine worms, and Madre, and evaporation far exceeds the rainfall. This small crustaceans. P. setiferus reach adult size after creates hypersaline conditions during dry years. It is nearly a year in the sheltered bays, and begin their not uncommon to encounter salinities in the 40 to 60 annual spring migration back to the open Gulf, using ppt range and in excess of 100 ppt in isolated ponds. channels and passes through the barrier islands. The Corpus Christi Bay and Aransas Bay systems Adult shrimp feed on organic materials that they find are connected by a ship channel which runs from the in the surface layer of the offshore sediments. This west end of Corpus Christi Bay to the junction of the organic material, called detritus, is made up of rotting Lydia Ann Channel. This channel is connected to the vegetation swept out of bays by tides . It also includes Gulf of Mexico by a natural pass through the barrier remains of other marine plants and animals that have islands. The channel is maintained at an authorized a role in the marine food chain. depth of 45 feet. It has been dredged through a hard This is a typical estuarine life cycle. It is clay substrate and is shaped line an open “U”. exhibited by the majority of important commercial All the sampling that takes place on the R/V and sport species of fish, crabs, and shrimp found off KATY trips occurs behind the barrier islands. As the the Texas coast. name implies, barrier islands provide an effective barrier against storm surges during hurricanes, and can help prevent oil from entering the productive bay systems.

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