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Item Analysis of Populations of Sports and Commercial Fin-fish in the Coastal Bays of Texas(Texas Parks and Wildlife Department, 1968) Breuer, Joseph P.; Coastal Fisheries Project Reports 1968Juvenile game fish were sampled in 1968 in all Texas bay areas with 60 ft. bag seines; adult fish were sampled in Galveston Bay by drag seine and in Aransas Bay and the Upper and Lower Laguna Madre with trammel nets. A general and significant increase in the relative abundance of juvenile redfish, Sciaenops ocellata, was noted. In the case of trout, Cynoscion nebulosus, flounder, Paralichthys lethostigma, black drum, Pogonias cromis, and sheepshead, Archosargus probatocephalus, there was either a decline in general abundance or no significant change from the previous year. While variations in abundance of adult fish occurred within bays, no coastwide patterns could be discerned. These samples were obtained in order to determine relative abundance, seasonal fluctuations in abundance and success of spawning. Captured fish of sufficient size and in good condition were tagged and released to study movements, migrations and rate of fishing harvest.Item Biological Survey of the Commercial Shrimp and Associated Organisms in the Inshore Gulf of Mexico - Study of the Texas Shrimp Populations(Texas Parks and Wildlife Department, 1964) Compton, Henry, Jr.; Texas Parks & Wildlife Coastal Fisheries Project Report 1964Regular stations were set up for weekly samples in the inshore Gulf off Port Aransas, Texas, in depths of 2 to 15 fathoms, in the inshore Gulf off of Port Mansfield, and Port Isabel, Texas for monthly samples in 2 to 20 fathoms, and in the inshore Gulf off Galveston samples under 10 fathoms annually. Brown shrimp, Penaeus aztecus, were very abundant in the southern Gulf off Port Isabel in May and were predominantly undersize; this same situation existed in June in the Gulf off Port Aransas. Significant numbers of white shrimp, P. setiferus, were found off Port Aransas in January when most were undersize. Pink shrimp, P. duorarum, were most abundant in May off Port Isabel. Seabobs, Xiphopeneus kroyeri, were abundant in January off Port Aransas and were not taken in the southern zone. Abundance of the various species was not noticeably different from that of 1963. Salinity and temperature were similar to those of 1963. Undersized brown shrimp could profitably be protected in the southern waters beginning in May and beginning in June off Port Aransas. Protection of small white shrimp in the southern waters at any time is probably unnecessary, although protection is indicated for the inshore gulf off Port Aransas in January.Item Checklist of fishes of Area M-3(Texas Game and Fish Commission, 1959) Hoese, H.D.; Texas Game and Fish Commission Marine Lab Project Reports 1958-59Monthly fish collections were made with seines, nets, trawls, etc. at various stations throughout East Bay, West Bay, and lower Galveston Bay (Area M-3), Texas. Associated data on hydrography and other environmental parameters were also recorded. These data serve to document the occurrence, relative abundance, and life history of fish species in the study area, as well as their relationship to hydrography.Item Checklist of Invertebrate Animals; Abundance and Distribution with regards to Hydrographic Conditions - Biological Survey of Area M-2(Texas Game and Fish Commission, 1961) Pullen, Edward J.; Texas Game and Fish Commission project reports, 1959-60Stations were established in Upper Galveston and Trinity Bays to determine invertebrate animals present, periods of their presence, their relative seasonal abundance, and their distribution relative to hydrographic factors. Emphasis was placed on shrimp occurrence and movement.Item Collection and Identification of Vertebrate Forms Present in Area M-2 and Determine Their Relative Seasonal Abundance - Ecological Survey of Area M-2(Texas Game and Fish Commission, 1960) Pullen, Edward J.; Texas Game and Fish Commission project reports, 1959-60.Objective: To determine the vertebrate forms present, periods of presence and relative seasonal abundance in Area M-2.Item Coordination of the Blue Crab Studies of the Texas Coast(Texas Parks and Wildlife Department, 1964) Childress, U.R.; Texas Parks & Wildlife Coastal Fisheries Project Reports 1963Commercial production was reported from three areas: Galveston, Matagorda, and Aransas. Production increased to over twice the production of 1962 in the Galveston area, while decreasing approximately one third in the Matagorda and Aransas areas. A total of 1307 samples were used to obtain information for this report. Of these, 734 were trawl samples, 188 trammel, gill or drag seine samples, 385 were seine or pull seine samples. These samples caught 5064 blue crabs. There were 2477 males (49.1%) and 2569 females (50.9%). This is 39.4% less than was caught in 1962 (8328 crabs).Item Coordination of the Blue Crab Studies of the Texas Coast - Studies of the Blue Crab Populations of the Texas Coast(Texas Game and Fish Commission Marine Laboratory, 1963) Childress, U. R.; Texas Game and Fish Commission Marine Fisheries Project Reports 1961-1962This report is compiled from a total of 1307 samples. Of these 878 were trawl samples, 151 trammel or gill net samples and 278 seine samples. A total of 11,097 blue crabs were taken in these samples during the study period. There were 5,680 males (51.185%) and 5417 females (48.814%). Twice monthly sampling of blue crabs in the Texas Bays in 1961 and 1962 confirms there are at least three waves of juvenile blue crabs spawned and possibly more are indicated in some areas. Growth rates ranged from 10.1 mm per month to 16.2 mm per month with an average monthly growth rate of 13.1 mm for the year. A peak abundance was found from April to June with a lesser upper peak on the upper coast in November which was not present on the lower coast.Item Factors affecting the community composition of epibenthic and infaunal invertebrates of newly planted seagrass beds(1999 1998 Mar 26) Henderson C;Epibenthic and infaunal organisms represent an important link between macrofauna and the seagrass beds they utilize. For this reason, benthic organisms should be considered when a comparison is made of the structural and functional equivalency of planted beds and natural seagrass beds. Three Halodule wrightii beds were planted during May 1994 in western Galveston Bay, Texas. The experimental design allowed for evaluation of water depth, planting density, and distance to edge on benthic community composition. Bare sand adjacent to the planted sites and a natural seagrass bed 15 km southwest of the planted sites were used for comparison. Monthly cores 10 cm diameter by 5 cm deep were taken for 16 months after beds were planted. Excluding decapods, invertebrates were identified to species when possible. Although species richness and abundance within the planted seagrass beds increased relative to adjacent sands, epibenthic and infaunal communities did not closely emulate those of the naturally occurring seagrass bed. Preliminary data indicate planting density had a positive effect on faunal densities, while water depth and distance to edge had no effect. Planted seagrass beds often take 2-3 years to reach shoot and root densities comparable to those of naturally occurring beds. Benthic communities in planted beds probably take at least as long to reach structural equivalence with those in natural seagrassesItem Factors affecting the community composition of epibenthic and infaunal invertebrates of newly planted seagrass beds(1999 1999 Mar 25) Henderson C;Epibenthic and infaunal organisms represent an important link between macrofauna and the seagrass beds they utilize. Consequently, benthic organisms should be taken into account when assessing the structural and functional equivalency of planted beds in relation to natural seagrass beds. Three Halodule wrightii beds were planted during May 1994 in western Galveston Bay, Texas. The experimental design allowed for evaluation of the effects of relative water depth, planting density, and distance to edge on benthic community composition. Bare sand adjacent to the planted sites and a natural seagrass bed 15 km southwest of the planted sites were used for comparison. Monthly cores 10 cm (id) by 5 cm deep were taken over a 16 month period after beds were planted. Organisms were enumerated and identified to species when possible which yielded 164 species or taxonomic groups. Annelids (Classes Polychaeta and Oligochaeta) were the dominant organisms in both planted and natural beds and defined most of the trends observed in the final analysis. Although species richness and abundance within the planted seagrass beds increased relative to adjacent sands, epibenthic and infaunal community densities and species composition did not reflect those of the naturally occurring seagrass bed even after 16 months. Of the three seagrass planting densities (0.25, 0.50, 1.00 m centers), 0.25 m centers contained the highest numbers of individuals and species. Distance to the edge of the planted sites had no effect on benthic community composition. Numbers of individuals and species were negatively related to water depth. When water depth and planting density interactions were considered, shallow water with 0.25 m centers had the highest abundance of organisms, whereas deeper water with 1.00 m centers had the lowest (difference between shallow and deep = 15-20 cm). Given the best circumstances, it will probably take the benthic community of a planted seagrass bed at least 2-3 years to compare with that of a naturally occurring bed. Maturation of the planted seagrass, as well as the benthic community, could be enhanced with a suitable planting design which takes into account planting density and water depthItem Interim Shrimp Study - Oyster Investigation, Area MO-1(Texas Game and Fish Commission, 1960) Shidler, Jon K.; Texas Game and Fish Commission project reports, 1959-60.Objectives: To provide a record of distribution, size, and relative abundance of shrimp species and other organisms taken in an otter trawl in the Galveston Bay system during the interval in which fisheries biologists were lacking in Areas M-2 and M-3.Item Oyster population trends in Galveston Bay, 1973-1978(Texas Parks and Wildlife Department, Coastal Fisheries Branch, 1983) Hofstetter, R.P.;Severe flooding on the Trinity River in 1973 destroyed oyster (Crassostrea virginica) populations in Trinity Bay and damaged those in the major harvest area in central Galveston Bay. Recovery was slow. Poor reproduction during 1975, 1976 and 1977 caused near depletion of oyster populations by spring 1978. However, abundant spat setting during 1978 resulted in an increase in small (seed) oysters in fall. Because market size oysters were scarce and seed oysters vulnerable to damage from oyster dredging, oystering in Galveston Bay was prohibited by proclamation of the Texas Parks and Wildlife Department (TPWD) effect 15 December 1978. Seasonal oyster harvests from public reefs in Galveston Bay ranged from 1.1 million kg (2.4 million lb) during 1976-77 to 8.7 thousand kg (19.2 thousand lb) during the abbreviated (45 day) 1978-79 seasons. As market oysters became scarce in Galveston Bay, oystering increased in mid-central bays. During the 1978-79 season, San Antonio Bay became the leading oyster producing area. The harvest of 359.5 thousand kg (792.7 thousand lb) established a record for that bay system. Private oyster lease production (confined to Galveston Bay) set a new record of 5861 meters cubed (7666.2 yards cubed). During 1976 only to be broken in 1977 when 7261 meters cubed (9497.4 yards cubed) were reported. Over a 23-year period, a decline in sample abundance of spat and small oysters has been observed although market oyster stocks remained relatively constant. A relationship between spring salinity values and spat setting was noted. Best spat sets usually occurred when salinity ranged 17-24 parts per thousand during spring. When salinity fell below 8 parts per thousand substantial spat sets did not occur.Item Population Studies of the Blue Crabs of the Galveston Bay System(Texas Parks and Wildlife Department, 1964) Moffett, Alan W. and More, William R.; Texas Parks & Wildlife Coastal Fisheries Project Reports 1963A major peak of apparent abundance of small blue crabs occurred in tertiary bays in the fall of 1963. Sampling indicated that sex ratios of juveniles were stable at each salinity level, while adults showed greater variation. All but 9 of 18 Gulf crabs (Callinectes danae) were collected in salinities over 20 ppt. Tagging results are discussed and suggestions to improve the experiments are offered.Item Population Studies of the Blue Crabs of the Galveston Bay System - Studies of Blue Crab Populations of the Texas Coast(Texas Game and Fish Commission Marine Laboratory, 1963) Pullen, Edward J.; Texas Game and Fish Commission Marine Fisheries Project Reports 1961-1962Trawls, seines, and trammel nets were used to sample the Galveston Bay crab populations. The data collected were used in determining the seasonal abundance of the crabs as compared to previous years' sampling. Blue crab populations in 1962 appeared to be larger than in 1961. The female population lagged behind the male in abundance in all months in 1962 except April, October, and December. The movement of adult crabs appeared to be governed by their search for food, reproductive cycle, and seasonal temperatures. Juveniles remained in the bay all seasons, moving toward the primary bay as they grew. Growth rate of the juvenile crabs was 0.4mm per day.Item Population Studies of the Sports and Commercial Fin-Fish and Forage Species of the Galveston Bay System(Texas Parks and Wildlife Department, 1964) More, Bill; Texas Parks & Wildlife Coastal Fisheries Project Reports 1963Seasonal occurrences, size ranges, and distribution of forage fish, juvenile game fish, and adult game fish in various habitats of Galveston Bay were studied. Forage species were most abundant in spring and least abundant in winter. Most species occurred during summer and fall. Juvenile spotted seatrout, Cynoscion nebulosus, black drum, Pogonias cromis, and redfish, Sciaenops ocellata, were more abundant at nursery areas sampled in 1963 than in 1962. Atlantic croaker, Micropogon undulatus, and sheepshead, Archosargus probatocephalus, were the most abundant adult game fish collected. Game fish tags were returned at a slower rate in 1963 than in previous year.Item Studies of the Blue Crab in Texas(Texas Parks and Wildlife Department, 1966) More, William R.; Texas Parks & Wildlife Coastal Fisheries Project Reports 1966Blue crab, Callinectes sapidus, populations were studied in eight coastal bays of Texas and in the Gulf near Bolivar Peninsula. In 1966, young crabs were more abundant in Aransas Bay and the upper Laguna Madre than at any time since 1962. Observable abundance changes were not apparent in other bays sampled. Galveston Bay fishermen produced 50% of the commercial blue crab catch. Total landings decreased 24% from 1965. Spawning and seasonal occurrence is discussed.Item Study of Texas Shrimp Populations, 1970(Texas Parks and Wildlife Department, 1969-70) Moffett, Alan W.; Coastal Fisheries project reportsIn spring, samples were taken with bar-seines and trawls from Sabine Lake, Galveston Bay, Matagorda Bay, Aransas Bay, and the Lower Laguna Madre to study brown shrimp (Penaeus aztecus) growth, movements, seasonal abundance trends, and environmental needs. The shrimp was abundant in samples from Galveston Bay, Aransas Bay, and the Lower Laguna Madre. Slow growth of juveniles during April in upper coastal bays was attributed to low temperature. Many, however, were 70 to 80mm long by late May, because growth accelerated as bays warmed.Item Study of the bay populations of juvenile shrimp, Penaeus aztecus, Penaeus setiferus. Period covered: January 1, 1961 - December 31, 1961(Texas Game and Fish Commission, Marine Laboratory, 1962) Compton, Henry; Texas Game and Fish Commission Marine Fisheries Project Reports 1960-1961This report is based on a totalof 542 samples, 29063 brown shrimp and 14,569 white shrimp. Semi-monthly sampling of juvenile shrimp in Texas bays in 1961 confirmed that there are at least three waves of juvenile brown shrimp, Penaeus aztecus, and white shrimp, Penaeus setiferus, entering bay nursery habitats. The greatest abundance of juvenile browns occurred in May and June, whereas juvenile whites were present in fair numbers from July through December. Growth rates during July and August were highest for both species, with that for browns computed up to 1.5 mm per day and that for whites up to 1.8 mm per day. A sharp drop in abundance of both species in the bay this year was reflected later in almost direct proportion to the Gulf commercial catch. Bay environmental conditions possibly affecting abundance of at least the brown shrimp include higher river runoff, lower bay salinities, and lower bay water temperatures at a time when most of the larval browns were entering nursery areas. It is more probable, however, that some adverse condition in the Gulf was the main cause of the poor shrimp production of 1961. It was again found that in many shallow, tertiary bays and bayous shrimp do not reach the proper size for harvesting.Item Study of the Blue Crab in Texas(Texas Parks and Wildlife Department, 1966) More, William R.; Texas Parks & Wildlife Coastal Fisheries Project Reports 1965Information on seasonal abundance, growth, movements and environmental relationships was used to study trends in the blue crab (Callinectes sapidus) population of Texas, while a survey of the commercial fishery was made to determine the size of the catch and market conditions.Item Study of the Fishes of Upper Galveston Bay - Ecological Survey of Area M-2(Texas Game and Fish Commission, Marine Laboratory, 1962) Pullen, Edward J.; Texas Game and Fish Commission Marine Fisheries Project Reports 1960-1961Forage fish and juvenile game fish samples were taken regularly with standard trawls and seines, while trammel nets, gill nets, beach seines, and rod and reel were used extensively to sample adult game fish. Hydrographic and climatitological data were collected in conjunction with each sample to correlate these factors with the seasonal abundance, occurrence, and distribution of the collected vertebrates. Three hundred and thirty samples were made, resulting in the collection of over thirty thousand fish. Ten new species and one species, last collected two years ago, were recorded in this year's checklist, while nineteen species collected or observed last year were missing. Anchovies, croakers, and sand trout, respectively, were the most abundant forage species in the collections. Game fish seemed to be more abundant in the bays in 1961 than in 1960. A total of 580 redfish, sand trout, speckled trout, drum, sheepshead, and flounder were tagged for growth and migration studies. Spawning and/or nursery habitats of these species were located and plotted. Population mass and species composition varied with the seasons. The summer populations were usually large and predominantly marine, while the smalled winter populations were generally a mixture of fresh water and marine species.Item Study of the Hydrography and Meteorology of the Texas coast - Analysis of Populations of Sports and Commercial Fin-Fish and of Factors Which Affect These Populations in the Coastal Bays of Texas(Texas Parks and Wildlife Department, 1965) Schultz, Ronnee L.; Texas Parks & Wildlife Coastal Fisheries Project Report 1964Each bay area along the Texas Coast is an entity with its own particular hydrographic problems. Tha Galveston, Matagorda and San Antonio Bay Systems have an average annual rainfall in excess of 25 inches, plus large river drainage systems which tend to maintain relatively low salinities. From Aransas Bay to the Laguna Madre, rainfall decreases to less than 20 inches and hypersalinity becomes a problem. Fisheries landings indicate that hydrographic conditions affect the productivity and abundance of shrimp, crab and some species of fish. During drought periods salinities become high and catches decline, while during periods of normal rainfall salinities become comparable to those of true estuarine systems and catches increase.