Another theory explaining decrease in duck, geese populations in SW. La
Published 8:22 pm Sunday, February 11, 2018
<p class="p1">Since last week’s column about a reason for a lack of ducks in Southwest Louisiana, several other theories have been forwarded.</p><p class="p1">One comes from Dr. Jay V. Huner, a retired professor at the University of Louisiana-Lafayette who is recognized worldwide for his research on crawfish as well as his position as a bird watcher of note.</p><p class="p1">He wrote: </p><p class="p1">“The observations about changes in rice cultivation in Sunday’s paper were interesting, but I tend to think they are well intended but off the mark. My associate Mike Musumeche (a certified ornithologist and retired biology teacher) and I have monitored water bird use of the working wetland landscape in southern Louisiana for over 20 years. Ironically, the attached report was precipitated by comments by a (Louisiana Department of Wildlife and Fisheries) biologist suggesting that crawfish systems within the rice/crawfish working wetland landscape were poor waterfowl habitat. </p><p class="p1">“I surely agree that there are differences in the physical characteristics of short-, medium- and long-grained rice varieties. But the overall culprit reducing waterfowl numbers in Louisiana is warming.</p><p class="p1">“Waterfowl need food and water. Neither is available when the landscape is frozen. In the past decade the birds have been short-stopped in the Missouri/Arkansas/Illinois/Kentucky/Tennessee/northern Mississippi region.</p><p class="p1">“They have plenty of food in ag fields and large lakes and reservoirs to provide water because those areas haven’t been frozen, at least, well into January.</p><p class="p1">“One of the reasons why working wetland hunters see birds show up immediately after the season ends is that the birds can detect changes in activity. When the hunters are out, the birds go find safe places.</p><p class="p1">“The situation is complicated. But, changes in the rice varieties is surely not as important as your contact seems to believe. That is, at least in our opinion.”</p><p class="p2">l</p><p class="p1">This is the report that Huner and Musumeche prepared on ducks and crawfish systems:</p><p class="p1">“We have been surveying water birds in working wetlands since the late 1980s. Waterfowl are of special interest because of the moneys associated with hunting them, especially in Louisiana. </p><p class="p1">“Working wetlands are agricultural areas managed for rice, crawfish, crawfish/rice, and finfish, specifically catfish. Working wetlands associated with rice and crawfish are generally shallow, often less than a foot deep and not permanently flooded. Those associated with catfish are deep, often four feet deep or more and permanently flooded. </p><p class="p1">“In Louisiana, there have never been more than 15,000 acres of catfish impoundments and today (2018) there are very few acres involved in catfish culture. Conversely, there are approximately 450,000 acres devoted to rice cultivation and, generally integrated into the landscape, 225,000 acres of crawfish. </p><p class="p1">“The rice-crawfish working wetland landscape is concentrated in the prairie region of Southwestern Louisiana, especially Acadia and Jefferson Davis parishes. There is also significant rice-crawfish activity in south-central Louisiana in the prairie region and in association with bottomland hardwood areas along the Atchafalaya, Red, and Mississippi rivers. </p><p class="p1">“Crawfish systems are generally flooded during the September-November period and drained during the April-June period but may have water in them for 12 months before being drained. Rice systems are generally flooded from March through September depending on whether one crop or two crops are cultivated. As a result, the southern Louisiana wetland landscape has water present year round. This provides habitat for resident and/or breeding Fulvous Whistling-Ducks, Black-bellied Whistling-Ducks, Wood Ducks and Mottled Ducks. This habitat is especially critical because thousands upon thousands of acres of adjacent natural wetlands have disappeared during the past half century.</p><p class="p1">“With the loss of adjacent natural wetlands, working wetlands welcome thousands of blue-winged teal and early migrant northern pintail and northern shovelers in the late August-late September period. Beginning in mid-late October, the bulk of migrant ducks, puddle ducks and diving ducks arrive and use the working wetland habitat which, for the most part, is crawfish impoundments. They continue into March when most begin their northward migration to breeding grounds. </p><p class="p1">“Geese, mostly snow and greater white-fronted, use the working wetland landscape to varying degrees from mid-October into mid-February before beginning their return to breeding grounds.</p><p class="p1">“Our observations are based on regular biweekly surveys in the Church Point, Mouton Cove and Catahoula regions along with numerous miscellaneous observations in the Sorrento and Bunkie regions. We are providing this discourse because there are those who question the value, specifically, of crawfish systems as waterfowl habitat.</p><p class="p1">“We have been having milder winters during the past decade. As a result, many ducks and geese that would otherwise come to southern Louisiana remain in the Missouri-Kansas-Illinois-Kentucky-Tennessee-Arkansas-northern Mississippi region well into the winter. They have plenty of food in ag fields and open water in reservoirs constructed in the past 50-60 years. They won’t move south unless the fields and reservoirs are frozen. So, there are fewer birds to be seen.</p><p class="p1">“Waterfowl are quick learners. If they survive one hunting season, they recognize hunters’ blinds and react to activity associated with hunters going into the field. Young birds are more vulnerable to hunters. But, the ratio of young birds has been low for some years now. As a result, older, savvy birds are going to respond to hunting pressure by changing their behavior patterns. That is, they become nocturnal, moving into the working wetland landscape at night while the hunting season is underway.</p><p class="p1">“Hunting pressure in the working wetland region is high because, despite reported poor hunting success, there are individuals who will pay $5,000-plus for hunting leases. It is the rare land owner, often not the individual who farms the land, who turns down the offer to lease a property. Again, the birds simply change behavior. In fact, National Wetlands Research Center studies using Doppler radar clearly show ducks moving north out of the marsh after dark to working wetlands and returning well before dawn!</p><p class="p1">“With 225,000 acres of working wetlands flooded for crawfish during the fall-winter-spring, waterfowl are spread out. This represents habitat dilution. </p><p class="p1">“So, are crawfish systems outstanding waterfowl habitat? They may not be ideal but waterfowl need both places to rest and to feed. Within the working landscape we have recorded large numbers of both puddle ducks and diving ducks. Likewise, we have found large concentrations of snow geese and greater white-fronted geese. So, maybe crawfish systems aren’t ideal waterfowl habitat but they are important waterfowl habitat.”</p>
