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The Bonnet Carre' Spillway diverts water from the Mississippi River through a floodway into brackish Lake Pontchartrain to reduce river stages at New Orleans and prevent flood damage. Pallid Sturgeon Scaphirhynchus albus, a federally listed species under the Endangered Species Act, and Shovelnose Sturgeon Scaphirhynchus platorynchus, listed under the Similarity of Appearance rule, are entrained through the spillway structure and become trapped in the canals and shallow lakes. The two species of sturgeon were identified according to a suite of morphomeristic characters, not genetically, and were therefore noted as either Shovelnose Sturgeon or presumed Pallid Sturgeon. Rescue efforts were undertaken to return the entrained sturgeon back into the Mississippi River. This article describes the environmental and operational conditions that influence entrainment risk, catch, and potential impacts on the population. Five openings and corresponding rescue operations occurred between 2008 and 2019 after each spillway closure. A total of 70 days with a crew number ranging from 6 to 12 were expended to collect 57 Pallid Sturgeon, four of which were dead, and 362 Shovelnose Sturgeon, 83 of which were dead, after the five openings that spanned 240 total days. More sturgeon were entrained at higher water temperatures, with a greater number of bays opened for longer durations. Recovery of sturgeon is initially high but over time declines as sturgeon are depleted from the floodway, stranded in isolated waterbodies in the floodway, and/or displaced further downstream into Lake Pontchartrain during longer openings. Sturgeon that cannot find their way back to the floodway are unlikely to be rescued. Recent population studies indicate that only a small proportion of the Lower Mississippi River total population is entrained. However, this does not take into account those individuals entrained but not captured and the potential impacts if more frequent openings of the structure were to continue in the future. Conservation recommendations are provided to increase catch efficiency and recovery of the endangered sturgeon. [ABSTRACT FROM AUTHOR]

Climate change forcings are having significant impacts in coastal Louisiana today and increasingly affect the future of New Orleans, a deltaic city mostly below sea level, which depends on levee and pumps to protect from a host of water-related threats. Precipitation has increased in the Mississippi River basin generally, increasing runoff, so that in recent years the Mississippi River has been above flood stage for longer periods of time both earlier and later in the year, increasing the likelihood that hurricane surge, traditionally confined to summer and fall, may compound effects of prolonged high water on river levees. The Bonnet Carré Spillway, just upstream of New Orleans has been operated more often and for longer periods of time in recent years than ever before in its nearly 100-year history. Because all rain that falls within the city must be pumped out, residents have been exposed to interior flooding more frequently as high-intensity precipitation events can occur in any season. A sustainable path for New Orleans should involve elevating people and sensitive infrastructure above flood levels, raising some land levels, and creating water storage areas within the city. Management of the lower Mississippi River in the future must include consideration that the river will exceed its design capacity on a regular basis. The river must also be used to restore coastal wetlands through the use of diversions, which will also relieve pressure on levees. [ABSTRACT FROM AUTHOR]

Provides information on the cane, Arundinaria gigantea monopodial bamboo found along Bayou Duplantier in Baton Rouge, Louisiana. Understory vegetation associated with the cane; Size of the cane; Growth of the culms.

Monotypic stands of cane (Arundinaria Michx.) known as canebrakes were a dominant landscape feature in the southeastern United States at the time of European settlement. Canebrakes disappeared rapidly as a consequence of altered fire regimes, agricultural clearance, and overgrazing by livestock, and are now regarded as critically endangered ecosystems. Canebrake fauna remains incompletely known and recent biodiversity studies of this ecosystem are few. In an earlier paper we used historic and contemporary sources to reconstruct the faunal diversity of canebrakes. However, because information is fragmentary and often found in obscure historical sources, inadvertent omissions were unavoidable in our earlier report. We here revisit this topic, provide additional records of canebrake fauna, and discuss the importance of canebrakes to wildlife. We documented the occurrence of an additional 28 species of vertebrates in canebrake habitats, including one reptile, 20 birds, and seven mammals. Canebrake herpetofauna (amphibians and reptiles) remains poorly documented. Birds use canebrakes as nesting, foraging, and winter roosting habitat, probably consume cane seeds when available, and incorporate cane foliage in nests. Much of what is known about the mammalian fauna of canebrakes is heavily biased towards megafauna, although a small number of studies suggest rodent and insectivore diversity is comparable to other early and mid-successional habitats in the southeast. Canebrakes provide mammals with escape cover, maternal den sites, foraging habitat, and food in the form of foliage and seeds. We reiterate our earlier recommendation for region-wide faunal inventories of existing canebrakes to address deficiencies in our knowledge as highlighted in this paper. Baseline data generated by these studies, combined with information gleaned from the literature, will provide a means to rigorously evaluate future conservation and restoration efforts. [ABSTRACT FROM AUTHOR]