Beating the Birds
Wednesday, April 2, 2008
filed under: Birds
Blackbirds continue to be the most frustrating production issue facing many sunflower growers. A combination of cattail-choked wetlands with nearby ripening sunflower is a recipe for potential damage.
USDA Wildlife Services is the designated federal agency to protect agriculture against certain types of wildlife, including blackbirds. Wildlife Services will be increasing its field activities to minimize blackbird damage in the Dakotas in the 2008 season.
Phil Mastrangelo, the North Dakota and South Dakota director for Wildlife Services has outlined several programs for 2008 that are different from past years.
Eliminating Cattails
Mastrangelo stresses that the first line of defense is eliminating cattails from wetlands. “Cattails are the perfect habitat for nesting blackbirds in the spring breeding season and migrators in the fall,” Mastrangelo points out. Wildlife Services has been spraying a labeled herbicide on cattails for several years and has resources to spray from 6,000 to 8,000 acres annually, thanks to Senate Appropriations Committee members Sens. Dorgan (ND) and Johnson (SD). “We [initially] directed the program to large wetlands of 10 or more acres, but are now taking smaller wetlands of several acres — especially if they are contiguous in a quarter or section,” Mastrangelo notes.
Another change this year is that USDA will spray out all of the cattails in a privately owned wetland, as opposed to the 70% in the past. This will provide longer protection against regrowth and give better protection against larger flocks.
For individuals concerned that too many cattails will be eliminated, Mastrangelo is quick to point out that there are well over 550,000 acres of cattail-infested wetlands in the Dakotas. “We are just making a small dent and selecting those wetlands that contribute to crop damage,” he says.
Mastrangelo stresses that applications are now being accepted, and he urges interested growers to call his office (701-250-4405) for applications. Or, go online at www.sunflowernsa.com under the grower section to obtain the application. Of course, growers can control their own cattails as well, and that is cheap insurance against this pest.
Federal or state-owned or -leased wetlands are eligible for cattail control as well, according to Mastrangelo. It will require contacting the federal or state wildlife office for permission; but he indicates in most cases they have been supportive of cattail reduction. For these wetlands, the 70% control threshold will continue.
Fieldmen, Cannons & Guns
The second line of defense is minimizing early season damage. That starts after petal drop and continues until the blackbirds group and begin the migration process. These early birds are often in small groups and have flying limitations due to immature growth of feathers.
Propane cannons placed in a field early are a good defense. Mastrangelo’s group will have several hundred “loaner” cannons complete with automatic timers. “The timers are really important, reports Stan Buxa of Harvey N.D. “I used the timers last year for the first time. They automatically turn off at night; and I alternated the timing sequence during the season. I still had propane in the first tank after the season was over. And it really worked! I got the cannons out early, and they did the job. The automatic timers are key, and moving the cannons periodically helps as well.”
Placing timers on existing cannons is easy, according to Mastrangelo. The best source to buy cannons and timers is Reed Joseph & Co. (800-647-5554). To further accentuate the power of the cannons, some growers point them into an empty 55-gallon drum. This provides a louder and sharper “boom.” Federal and state laws allow producers to shoot birds that are damaging their crops; the addition of lethal control reinforces the effect of frightening devices.
Mastrangelo will have five or six fieldmen located throughout the problem region of the Dakotas from July through October. He has additional full-time people to help out if the fieldmen get behind. They will respond to grower calls in their area, delivering cannons and providing harassing assistance as time allows. “But we really want to eliminate the cattails in these areas as much as possible, because that will make everyone’s job easier,” Mastrangelo states. Fieldmen’s phone numbers will be posted on NSA’s website and also mailed to growers prior to the start of the season.
Conservation Lure Fields
USDA has been providing funds for the planting of lure fields to minimize damage in commercial fields. This program has been under a research protocol for several years, and it appears to have overall limitations in terms of a cost/benefit. However, USDA will work with groups of farmers who plan to plant acreage in a large block.
This concept was tested by a group of farmers near Lakota N.D., and was successful. “The lure field concept appears to have application in this kind of setting,” Mastrangelo indicates. He should be contacted to explore the funding of lure fields when an acreage block is being considered.
Late-Season Migrations
Blackbirds migrations usually start after the first hard freeze in late September or early October. These birds are on their way south, and will stop at fields along the way if the proper combination of cattails and water is nearby. Mastrangelo will combine all of his personnel resources if a grower is hit with a large influx of migrators. “We will bring in teams to move those birds out of that wetland,” he emphasizes. “We are not going to leave a grower high and dry, fighting a huge influx of 10,000 or more birds by himself. If necessary and a last resort, we will bring in aircraft on a cost-share basis to assist in moving the birds out.” The key here is contacting the central office (701-250-4405) or the affected area’s fieldman.
Desiccation
This is the other major tool in eliminating blackbird damage. Getting the crop off up to 10 days earlier is like a month in the late season, according to Dr. Burton Johnson of North Dakota State University.
Glyphosate is now labeled as a late-season weed control — and the side benefit is that it desiccates as well. There has been considerable research on the use of glyphosate in multiple locations from North Dakota to Kansas. The label says to
spray at 35% seed moisture or less. Determining 35% seed moisture is one of the challenges in knowing when to pull the trigger. Not all hybrids look the same as they begin to dry down.
The label likewise mentions “bracts turning brown.” Longtime NDSU agronomist Duane Berglund uses the rule of “back of heads yellow and easily rubbing the florets off the face of the head” as another indicator of maturity.
There also are concerns on unevenly maturing fields. “This happens when plants emerge unevenly,” says NDSU’s Johnson, who has led a team on desiccant research for several years. “Our research indicates that there will not be any damage to seed size, oil content, test weight or yield when spraying at the 40% seed moisture level. The product is slow acting, so the plant will continue to mature.”
For a quick kill paraquat or Drexel Defol are the choices. One of the concerns about paraquat is that it works as a cell disruptor, which can actually add moisture to the plant head if rains occur between spraying and harvest.
The bottom line is to get the crop off as soon as possible if birds, wind or other late-season factors are a concern, says Bruce Due, Northern Plains district agronomist for Mycogen. “From my experience, in 2007 most farmers waited too long to spray — well after 35% seed moisture had been reached,” Due says. “In the northern region, we lose heat units quickly in late September — and glyphosate won’t translocate quickly enough to dramatically cut down the days to harvest.”
There’s also the issue of the new hybrids that have the “stay green” gene and indeed do stay green later into the season. Kevin Korus of Denhoff in central North Dakota noted that his 2007 crop had leaves on the plants and green stalks — but the seeds were dry. “It never froze last year, and I was not willing to wait for the usual freeze to start harvesting,” he says. “Harvesting worked fine despite the green plant material. I drove a bit slower and the combine squeaked a few times. Some of my neighbors may have thought I was a bit wacky, but it worked and I’ll do it again.”
Mycogen’s Due says that approach is becoming more common. For the producer who does not want to run green material through his combine, a paraquat or Defol application might be a good choice to burn off the leaves. But the key is getting that crop off as soon as possible to avoid bird damage.
Research & Other Options
NDSU will be accelerating its research this summer on how to use the avicide DRC 1339, which is fully labeled by the EPA for controlling blackbirds.
This will be the second year of the research, which will center on attracting blackbirds to a feeding platform. Last year’s study summary indicates that nontarget birds were a nonevent. There were no pheasants or doves using the trays. On the downside, it was challenge to lure blackbirds to the feeding areas in large numbers. Hot bait was utilized on a very limited basis.
Researchers are planning to make adjustments to cages in an effort to attract more blackbirds onto the feeding trays. If successful, Mastrangelo’s operational group will begin baiting immediately, since the product is labeled.
USDA will be testing several repellents in caged trials this spring. One product is already labeled for use, but there are no efficacy data available. The other product is experimental and is being tested on a number of crops.
Recently, a national meeting of affected crops, cities, health units and airports was held to discuss the problem of a North American blackbird population that is clearly out of hand. Blackbirds are a serious nuisance and a human and animal health hazard in many cities, feedlots and dairies. Of even greater importance is the safety issue blackbirds pose at many of the nation’s airports. There were reports of acres of trees removed strictly to eliminate blackbird roosts near airports.
A task force of impacted groups has been organized to generate greater public awareness of this issue. All of the impacted groups recognize that simply moving blackbirds from one spot to another is a failed course. Population management is the ultimate goal.
— Larry Kleingartner