Hollandse Delta protects dikes & tulips from rats with Bell's TOMCAT BLOX

In Holland, where the Dutch have spent centuries mastering the art of water management and tulip growing, an equal amount of skill goes into protecting these achievements from the ravages of rats.

While brown rats may not seem as formidable a threat as the sea in a country where more than half its land mass is at sea level, these burrowing pests could seriously jeopardize Holland's elaborate dikes and dune systems, as well as its lucrative tulip industry. That's why good water management in the Netherlands is as much about regulating water levels as it is about keeping brown rats, coypu, and muskrats from destroying canal banks, endangering dikes, and devouring tulip bulbs.

On any given day in the Delta region of southern South-Holland, Jan van der Baan and Gerrit Knipers can be spotted in their white van bearing the Hollandse Delta logo, as they respond to sightings of brown rats on the islands of Hoeksche Waard and Goeree-Overflakkee.

Knipers and van der Baan have been performing rat control services for the Delta's water authority, Waterschap Hollandse Delta, for more than a decade. Their work is so critical that the water authority posts their photo on its website homepage instructing residents to call the technicians if they spot rats. Rat control within a water company seems an unlikely match, but in Holland, water authorities leave nothing to chance when protecting its people from floods.

In fact, water authorities are Holland's oldest form of participatory democracy, dating back to medieval times when the Dutch people elected officials to oversee the management of water so everyone's water interests were met.  By the 1850s, 3,500 water authorities operated in Holland. Over the next century the number dropped to 2,500. In 1953, when a weakened, wind-pummeled dike in southwestern Holland broke, taking the lives of 1,835 people and forcing 100,000 others to evacuate their flooded island homes, many smaller water authorities merged to prevent any similar catastrophes in the future.

Today, there are only 25 water authorities, with Waterschap Hollandse Delta managing the five-island Hollandse Delta region. With most of the Delta area below sea level, the water authority safeguards 750 kilometers of dikes and dunes to protect the area's 825,000 residents from flooding. It regulates the level and flow of water through dams, locks and pumping stations and preserves the integrity of dikes and dunes from rodent damage.

For pest control technicians Knipers and van der Baan, an on-going part of their job is working with the provincial government and local authorities to control brown rats on the islands of Hoeksche Waard and Goeree-Overfflakkee. Rodent control on the other three islands is the responsibility of the local municipalities, while muskrats, another pest whose tunneling causes damage to dunes and dikes, are managed by Muskrat Control Boards that frequently hire trappers. "Prevention is better than cure," the technicians emphasize. "Rats can destroy dikes. Their extensive burrowing will cause dikes to collapse."

To stay ahead of the rats, van der Baan and Knipers have set up a baiting program that covers a 386 square mile system of canals. From October to March, they focus on protecting the dikes and dunes along the Delta Project, a mammoth engineering project nearly 30 years in construction, that protects Holland's coast from dangerous tidal floods while improving water balance.

Within their region, the technicians service thousands of Bell's PROTECTA LPs and PROTECTA Bait Stations placed along the dikes and sandy dunes, as well as in storage facilities, clubs, and roadhouses along the sea shore - anywhere rats create problems. On the advice of their rodent control products distributor, Bert Spierings of Riwa B.V., the technicians bait with Bell's TOMCAT BLOX* containing the active ingredient, bromadiolone. The extruded 28g and 225g BLOX hold up well outdoors.

Typically the men check bait stations at least eight times a year or more frequently, if an area shows increased rodent activity. "Their work is very important," noted Bell representative, Thomas Deuscher, who accompanied van der Baan and Knipers on their rounds in spring. "They bait to protect the construction of the dikes to prevent them from collapsing."

Protecting Spring Tulip Bulbs from Rats
Another key role for the pest control technicians comes in springtime when the Delta, one of three major tulip breeding areas in Holland, is a blaze of color from blooming tulip fields. Then the men take their work to the tulip fields, controlling rats that like to gnaw the new and precious bulbs.

Protecting new tulip bulbs is critical to Holland's economy where more than 10,000 hectares of the Dutch landscape produce nine million bulbs annually, two-thirds of them exported to Germany and the U.S. For Delta farmers, tulip cultivation represents a huge investment of time and work in developing new tulips. "With new bulbs, the first year, you get 10 bulbs. The second, maybe 50," Deuscher explained. "By the third year, 150 bulbs and in the fifth year, you'll have 500 new bulbs with a value of 50,000 Euros. It's a huge loss to loose bulbs."

To protect these special bulbs, van der Baan and Knipers place PROTECTA?Bait Stations directly in the service rows of tulip fields every six meters. In traditional tulip fields, which are 500 by 1000 meters, they may place as many as 2,500 bait stations, going through a pallet of TOMCAT BLOX every month, approximately 600 kilograms.
"Many years of research and development would be lost, if new tulip bulbs were destroyed by rats," Deuscher pointed out.

"With 500 tulip bulbs of a new cultivar valued at $75,000, you can imagine that pest control holds a special spot for farmers. And, without it, there would be no tulips on your desk at home." Routinely, the technicians also assist other farmers along the North Sea with infestations, such as in pumpkin fields - work Deuscher describes as "never-ending."  "This is strictly a maintenance program. If they didn't do their job, it wouldn't take longer than one year for the rat population to explode," he emphasized.

In addition, the technicians respond year-round to the 500 - 1,000 calls from the island residents who spot rats. "We have an educational task," they point out. "We give people tips to avoid the inconvenience of dealing with rats." Their vigilance, as Deuscher summarized, "protects the bulb growers acreage from rats which is a financial matter. Protecting the dikes to avoid collapsing guarantees 100,000 people in this area safe living."

* TOMCAT BLOX is sold under the CONTRAC BLOX label in the United States.