Robert H. Chabreck

A tank study was conducted to determine the effects various concentrations of crude oil on brackish marsh plants. Scirpus olneyi and Spartina patens were grown in tanks and subjected to a light and a heavy crude oil at four concentrations and four water levels over an H.5-month period. Growth and survival ofplants were detennined monthly. A fluctuating water level (+5 to -5cm) with so parts per thousand (ppt) of heavy crude oil was the treatment most detrimental to S. olneyi. Crude oil enhanced growth and survival of S. olneyi at a water level of +5cm above the soil surface. Growth...

Food preferences were determined for white-tailed deer (Odcoileus viginianus) in marshes and spoil arreas along the Louisiana coast by using feeding trials with captive deer and browse surveys. Fifty species were offered to 3 deer during the feeding trials. The species selected in largest amounts were Leploch/oa fascicularis, Scirpus olneyi, Iva annua, Echinochloa walteri, and Aeschynomene virginica. Preferred food plants during the browse surveys along marsh levees were Paspalum vaginatum, Mikania scandens, Bocapa monnieri, Panicum dichotomiflorum, and Leptochloa fascicularis.

Canada Geese were released on Rockefeller Refuge in Louisiana in 1960 in hopes of establishing a resident, non-migratory flock. One nest was constructed in 1961; however, the Dumber of nests increased each year and by 1973, 265 nests were located on the refuge. The geese became acclimated to the warmer southern temperatures and adjusted their nesting season accordingly. They tended to nest earlier in the year with succeeding nesting seasons. The earliest nesting date on the refuge was February 19, 1968. Parent geese were allowed to incubate the majority of the nests; however. eggs were...

Ducks were inventoried monthly over a 2-year period in order to compare usage of management units in the Louisiana coastal marshes. Areas inventoried were brackish and fresh water impoundments, which were managed for ducks. and marsh pump-out units, managed for beef cattle. In addition, natural marshes nearby were sampled as a control. Water depth readings were taken monthly and vegetation was sampled annually to provide information on factors affecting duck usage. Greatest duck usage was in the fresh water impoundments. but usage of the brackish impoundments was very similar to that of...

During the winter 1972-73, 1,000 Snow Geese (Chen caerulescens caerulescemp were captured and color-marked at Sabine National Wildlife Refuge in southwestern Louisiana and 592 at Anahuac National Wildlife Refuge in southeastern Texas to determine the distribution patternsand flock integrity. Over 450 subsequent observations of the marked geese on the wintering grounds showed that Snow Geese move considerable distances during the wintering season; most birds dispersed from the capture sites in an east-west direction. Geese from Sabine NWR were observed over an east-west belt 267 miles wide...

A plan was initiated in 1960 for establishing a local nesting colony of Canada geese (Branta canadensis) on Rockefeller Wildlife Refuge in Louisiana; however, little information was available on Canada goose nesting along the gulf coast. Previous reports on establishing local nesting populations dealt mostly with attempts in north central and northeastern states (U.S. Department of the Interior, 1958; Clark and Nightingale, 1960). Therefore, much of the earlier work on this project was experimental in nature. The purpose of this study was to compare the breeding behavior of Canada geese of...

Samples from fresh and saline waters in Louisiana showed little relation between foods eaten by young alligators and organisms available in these environments. Crustaceans were the principal foods in both freshwater and saline areas. Alligator stomachs from a freshwater area contained more than 6 times as much food as those from an adjacent saline area. The stomach capacity in the freshwater area was twice as great as in the saline area. The study suggests that young alligators which remain for extended periods in saline areas will have reduced growth rates as a result of reduced food...

A survey of the Louisiana Coastal Area disclosed that ponds and lakes made up one-fourth of the area. The ponds and lakes ranged from less than 0.01 acre to over 400,000 acres and numbered 5.3 million. The study shows that the fresh, brackish and intermediate marshes were of high value to waterfowl because of high pond density and plant growth. Ponds and lakes in the saline marshes were of low value to most waterfowl, but of extreme importance to marine organisms.