Testing the Goodnature E2 Rodent Trap in Tata Steel Zoological Park, India

IPCadmin | July 25, 2014

There are 4000 species of mammals, of which about 1700 are rodents. However not all rodent species are commensal pests. About 150 species have been defined as a commensal at some time or another, though only 20 could be termed important in connection with post-harvest losses. The number of species occurring in and around human habitation drops to below ten according to FAO (2014) and when it comes to the urban environment the number could be still lower.

The design behind the E2 arises from the management of rats in large scale Wilderness Conservation Programs. Thus it has minimal requirements for servicing, maximum reliability and simplicity, and repeated successful killing of rats and mice.

Rodents are possibly the most noteworthy pest to humans. They eat and contaminate food, damage structures and property, and transmit parasites and diseases to other animals and humans. They live and thrive in a wide variety of climates and conditions, and are often found in and around homes, buildings, gardens, various man-made structures, farms, open fields and forests. The ability to transport themselves with humans and in association with human driven activities has thus made them a cosmopolitan pest.

The trap is set live, powered by a compressed CO2 canister. The rat is attracted to the lure within the trap and enters to investigate.

As the rat attempts to reach the lure it brushes past the very sensitive leaf trigger activating the trap. The piston strikes the rats skull killing it instantly.

Control and management of rodents remains predominately a challenge with a need for continuous monitoring and intervention. Only rat proofing through physical methods has proven to be long-lasting. Other methods such as traps, baits and poisoning are labour intensive, messy and at times dangerous. The need for alternative solutions is at the forefront for every manufacturer, researcher and pest controller. This need has led to the development of a new humane, rodent control device, the Goodnature E2 Automatic Humane Rat and Mouse Trap marketed by Ensystex.

Rodents are attracted to the Goodnature E2 by a non-toxic food lure. The lure can be manually dosed or the user can use a local feed source known to be preferred by the target pest population. The E2 is powered by compressed CO2 from a small, recyclable canister. This powers and resets the trap multiple times before needing replacement. This is important since it ensures other pest rodents are can also be killed by the E2, providing continuous control. Field trials have proven that the E2 can kill several rodents in the one night, with rodents climbing over the bodies of other dead individuals to get to the lure.

The striker returns on a light spring. The dispatched rat drops to the ground. The trap automatically resets itself and continues to do so up to 24 times per gas canister.

Inside the E2, the precision designed internal pressure reservoirs are calibrated to 400 – 450 kPa. The toxin-free rodent lure is mounted above a shroud chamber. The lure draws the rodents in to investigate. When the rodent’s head is positioned correctly in the shroud chamber, it brushes aside a sensitive Leaf360 Trigger™, (set at a pressure of just 20g). This opens a cascade of valves and chambers, ultimately venting the gas from the internal reservoirs. The compressed CO2 then explodes into the piston bore, driving a glass reinforced polymer piston out, with a force of 30 Kg, instantly killing the target. With the internal pressure dropped, the canister releases more CO2, and the system once more closes off the piston bore, refilling the reservoirs. A small spring draws the piston back into the firing position. The E2 is now armed and ready to kill the next pest rodent. This means the E2 can effectively be set and left with no requirement for regular checking. Additionally, the E2 provides a humane kill of the rodents (NAWAC 2011).

Fresh lure continues to attract further rats into the trap allowing multiple kills per maintenance effort.

Testing E2 in Tata Zoological Park in India

Tata Steel Zoological Park, Jubilee Park, Jharkhand, India, an accredited zoo under the Indian Wildlife (Protection) Act, 1972 is operated by Tata Steel Zoological Society. The zoo is spread over an area of 90 acres with large spaces in the form of manicured lawns, gardens and forest patches. Animal enclosures occupy the rest of the space in the zoo. A majority of the animal enclosures are large, with a moat or fence barrier. The zoo campus is infested with bandicoots (Bandicota bengalensis), a species of field rat which is a major pest in India. Previously the pest was being controlled by baiting, poisoning and fumigation. However, their population could not be kept under check due to the large size of the campus and the inability of staff to execute the existing methodologies of rat control within the actual animal enclosures, due to the likelihood of primary or secondary poisoning of the valuable captive wild animals.

For the purpose of management, Tata Steel Zoological Park is divided in to four ‘Beats’. The entire zoo is home to field rats (bandicoots) with their maximum presence noted in Beat-1, where all the bird species are housed and displayed. Birds, like pheasants, have a particular tendency to spread and spill grains from feeding containers during feeding, which leads to the attraction of rats. Thus the pheasant enclosure was chosen as the site for the trial. The Goodnature E2 Trap was mounted on a wooden frame and placed inside the enclosure. Grains, as provided to the birds, were used to lure the rats to the E2. The E2 remained in the location for two weeks, after which the compressed gas canister had completely discharged. A replacement canister was mounted and the E2 was moved to a second location in the same enclosure. It remained there until the completion of the trial.

The placement of the E2 trap is deemed critical in maximizing the efficacy of the device. To ensure this the E2 was placed very close to rodent feeding points as determined by the presence of scattered grains and, or the presence of faecal pellets. Placement of the E2 on entry and exit points to the enclosure, runaways and exposed spots was avoided.

On the first night of its installation, 2 rats were killed. The dead rats were found next to each other with no visible signs of injury. The carcasses were disposed of, and the trapping work continued. A total of 22 rats were killed by using the technique with the use of one gas canister in one location. The second canister was mounted and trials continued. Fresh grains were added as the lure. During this second period, a total of 20 rats were killed. The canister was still active at the end of this period. Noticeably, multiple kills on the same night were again reported.

In total 42 rats were removed in 30 days from the bird enclosure, significantly reducing rodent activity, as evidenced by reduced visual sightings, an absence of rat droppings, and the absence of grain spills. However, in view of the large rodent population in the area, long term rodent management will depend on continuous use of the E2 and rat proofing the area. The zoo is presently considering a long term program with the Goodnature E2 device.

A report recently published by New Zealand Herald quoted Kevin O’Connor, Deputy Director General of the Department of Conservations – Conservation Services Group, describing trials using this device as “very promising and a significant step towards having a better and more effective and sustainable trapping option for predator control in New Zealand.” Similar reports of successful usage of the product by pest control practitioners in urban areas have been received and the first author is presently engaged in validating it with his own trials.

References:
*FAO, (2014). www.fao.org/docrep/t1838e/T1838E1K.HTM#Rodent species of postharvest importance.
*New Zealand Ministry of Agriculture, Farming and Fisheries, National Animal Welfare Advisory Committee – Class A Humane Standard (2011).
*New Zealand Herald (2014). www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11215053.

Authors:
Partho Dhang, PhD(1) and Bipul Chakrabarty (2)
(1)-Independent Consultant, 2410 Belarmino Street, Makati City, Philippines.
(2)-Director, Tata Steel Zoological Park, Jubilee Park, Jamshedpur-831001, India.

Published in International Pest Control – May/June 2014 issue.

Tags: Rodent Trap, Rodents