When the Crow's England Ravages the Garden
Harvest Ravaged by Crow Predation - Crow fever obliterates crop yields
Hey there! Get ready to dive into a tale about crows wreaking havoc on farmers' fields, leading the State Office for the Environment (LfU) to take action. In collaboration with the Weihenstephan-Triesdorf University of Applied Sciences (HSWT), they've launched a pilot project, testing various methods to minimize future damage linked to crow attacks.
This endeavor started way back in April, focusing on regions like Straubing, Erding, and Asbach-Baumenheim (Donau-Ries district). Farmers eager to join the project still have time. In Straubing, the crow colony, nesting near the Tiergarten, is estimated to house around 1000 breeding pairs, as per an LfU spokesperson.
Crows: High-end hamburger lovers
These winged beasts put such a strain on the land that some areas are barely able to grow crops due to their relentless assault. Crows aren't exactly vegetarians; they prefer animal proteins, like earthworms. If earthworms are scarce, they uproot plants and seedlings just to munch on the larvae nestled in the roots. They're also partial to pumpkin seeds and radish heads.
Conventional measures like scarecrows or reflective CDs hanging on wooden crosses don't always peel back the curtain of mystery surrounding cornswipe behavior. That's why, in the project areas, we see balloons, kites, and decoy crows in action, explains Nils Teufel, a scientific staff member at HSWT.
Feathers, brother, or pew-pew?
In Straubing, they're testing even bolder approaches, such as shooting. Exceptional licenses to lift the hunting ban have been granted by the city and district of Straubing. Raising heritage birds is off-limits in this experiment, and no crows have been shot since the project's inception.
Remember, crows are mighty smart birds, just like their rook cousins, so permits for shooting them must also be obtained on the project areas, says the LfU spokesperson, just in case a hunter accidentally blasts a raven instead.
Holes in protective mesh nets
One participant in Straubing's experiment is Johannes Frank, who grows medicinal plants like Primula veris, among other things. During a tour, he shows images of ruined fields. Believe it or not, protective nets over the young plants don't scare these feathered critters! They just poke holes in them with their beaks. Neither people nor vehicles can shoo them away; they simply follow the planter and yank out the seedlings again.
Tending the field requires six employees working from dusk till dawn for four consecutive days. The damage inflicted by crows can't be undone. Customers expect dependability, too!
In 2023, approximately 140,000 euros in damages were inflicted by crows at Johannes Frank's farm and three other cultivation operations of the Obst und Gemüse Straubing cooperative. Now, Johannes Frank has deployed special kites from LfU on his field, along with plastic decoy dead crows. These are designed to scare away crows, looking so alive that passersby have called the cops to report dead birds, as an LfU spokesperson mentioned.
Frank acknowledges a habituation effect with these deterrent methods, but he stresses the critical period is the initial 14 days after planting medicinal plants. This season, crows didn't adapt to the decoys as swiftly as in previous years. "No guarantees," notes Nils Teufel.
The project concludes at harvest and will be evaluated by yearend. In Dachau, within the LfU project, they've spent time deterring crows in urban areas, resulting in 14 crows being shot and 83 nests removed. Results from this part of the project are yet to surface.
Bavarian State Association for the Protection of Birds (LBV) voices opposition to the project, commenting, "We're observing a trend where, in situations involving conflict with wildlife, the call for culling arises swiftly. Instead, we should focus on finding solutions that take species and animal protection into account."
The crow's move into cities is a consequence of agricultural changes. Fewer undisturbed tree groves offer a suitable nesting site for colonies, according to the LBV. "The birds move into cities—often out of desperation."
Enrichment Data:
Overall:
Unconventional methods like kites, balloons, and crow decoys might scare away crows initially, but their effectiveness diminishes as birds adapt. These methods are easy to implement, but less reliable compared to more sophisticated deterrents like laser bird deterrents or automated scarecrow systems.
Kites, Balloons, and Crow Decoys:
- Effectiveness: Kites, balloons, and decoys can work initially due to their visual disturbance; however, crows can quickly habituate to them, reducing their long-term effectiveness. There's no specific data available for regions such as Straubing, Erding, and Asbach-Baumenheim, but their effectiveness likely varies based on crow populations and conditions.
- Advantages: These methods are relatively easy to deploy and can initially deter crows.
- Disadvantages: They may lose effectiveness over time as crows adapt.
Comparison to Other Methods:
- Laser Bird Deterrents: Lasers have demonstrated significant success in reducing crop loss, ranging from 30% to 60% down to 1% in some cases, compared to traditional scarecrows or kites. Lasers are more reliable, but may not be practical in all situations.
- Automated Scarecrow Systems: These systems include motion sensors, sound transmitters, and lights, working effectively over larger areas than traditional scarecrows. Although not specific to the project area, they might provide a more efficient and reliable solution than kites, balloons, or decoys.
- The State Office for the Environment (LfU) has launched a pilot project to minimize future damage caused by crow attacks, in collaboration with the Weihenstephan-Triesdorf University of Applied Sciences (HSWT), using methods such as kites, balloons, and decoy crows.
- In the project, kites, balloons, and decoys are used to scare away crows initially due to their visual disturbance, but their effectiveness diminishes as the birds adapt to these methods.
- Laser bird deterrents and automated scarecrow systems have shown significant success in reducing crop loss, demonstrating more reliability compared to kites, balloons, and decoys.
- The Bavarian State Association for the Protection of Birds (LBV) opposes the use of more conventional methods like kites, balloons, and decoys due to the potential for habituation and the need to focus on solutions that take species and animal protection into account.
