Evaluation of moderate and low-powered lasers for dispersing double-crested cormorants from their night roosts (original) (raw)
Related papers
Red lasers are ineffective for dispersing deer at night
Wildlife Society Bulletin, 2003
Populations oi white-tailed deer (Odocoileus virgirlianusi and the number o i deer-human conilicts have increased in recent years, emphasizing the need ior eiiicient and inexpensive methods to reduce site-speciiic deer damage. Recent research using laser technology to disperse a variety of bird species has yielded promising results, prompting wildliie proiessionals and the public to question whether lasers could play a role in reducing damage and conflict with mammals, primarily deer. We evaluated 2 red lasers (63-650 nm) to determine their efiectiveness as devices to frighten deer. No difierences occurred in ilight response hetween lasers or between the control and lasers. We suggest that deer \yere not irightened by either model o i laser because they could not detect red laser beams or their intense brightness. Red lasers do not appear to have potential as irightening devices ior deer.
Evaluation of lasers to disperse American crows, Corvus brachyrhynchos, from urban night roosts
International Journal of Pest Management, 2002
American crows (Corvus brachyrhynchos) have a long history of causing agricultural damage in North America. Shooting and bombing at crow night roosts have been employed to reduce such damage. Most roosts were located in rural locations, but in the latter half of the 1900s crows began to roost in urban locations. Urban crow roosts are presently a nationwide problem in the United States. Thousands of crows at a roost create problems for businesses and residents. Improved control techniques are needed. Lasers have been used in Europe to scare and disperse birds but the technique has only recently received formal testing. We treated urban roosts with lasers to determine if crows react to laser light, can be dispersed from roosts, and whether lasers are effective for eliciting roost abandonment. We treated 63 roosts in Woodland, California and recorded the immediate and short-term reactions of crows. We counted crows at five roosts in Davis, California during an 8-day pre-treatment period and then again during a 4-day treatment period to evaluate crow response to laser treatment. Crows reacted to the laser beam. In Woodland 100% of the crows flew immediately away from 49% of the treated roosts. Between 50% to 99% of all crows flew immediately away at 44% of the treated roosts. At 84% of the roosts crows left without vocalizing and at 95% of the roosts flew directly away without circling overhead. Crows returned to all roosts within 15 min. In Davis there was no difference in the number of crows using roosts during the pre-treatment versus treatment periods. Despite initial dispersal upon treatment, crows reoccupied all treated roosts the same night after treatment. No roosts were abandoned. Therefore, we do not recommend lasers as a stand-alone dispersal tool at urban crow roosts.
Green and Blue Lasers are Ineffective for Dispersing Deer at Night
Wildlife Society Bulletin, 2006
Over-abundant populations of white-tailed deer (Odocoileus virginianus) create agricultural and human health and safety issues. The increased economic damage associated with locally overabundant deer populations accentuates the need for efficient techniques to mitigate the losses. Although red lasers can be an efficient tool for reducing damage caused by birds, they are not effective for deer because deer cannot detect wavelengths in the red portion of the spectrum. No research has been conducted to determine if lasers of lower wavelengths could function as frightening devices for deer. We evaluated a green laser (534 nm, 120 mW) and 2 models of blue lasers (473 nm, 5 mW and 15 mW) to determine their efficacy in dispersing deer at night. Deer were no more likely to flee during a green or blue laser encounter than during control encounters. The green and blue lasers we tested did not frighten deer. (WILDLIFE SOCIETY BULLETIN 34(2):371-374;
Effectiveness of a Motion-Activated Laser Hazing Systemfor Repelling Captive Canada Geese
2005
Effective management techniques are needed to disperse Canada geese (Branta canadensis) and reduce the human-wildlife conflicts associated with high population densities. We evaluated the effectiveness of a motion-activated laser hazing system for repelling captive Canada geese. The system decreased occupancy of 8 pairs of geese on the treated subplot by 83% during habituation trials. When an additional pair of geese were added to the experiment, occupancy of the treated subplot decreased .92% during each of the 20 nights of the extended habituation test. Avoidance (conditioned during the test) remained ,80% of pretreatment levels during the 2 days immediately following the habituation test but extinguished 3 days subsequent to the permanent inactivation of the laser hazing system. The motionactivated laser hazing system effectively repelled Canada geese in captivity. Additional field research is needed to determine the spatial extent of the laser hazing system and the effectiveness of the Doppler radar motion detector for repelling wild geese. (WILDLIFE SOCIETY BULLETIN 34(1):2-7; 2006)
Scientific Reports
In the Netherlands, free-range layer farms as opposed to indoor layer farms, are at greater risk with regard to the introduction of avian influenza viruses (AIVs). Wild waterfowl are the natural reservoir hosts of AIVs, and play a major role in their transmission to poultry by contaminating free-range layer areas. The laser as a wild bird repellent has been in use since the 1970s, in particular around airfields to reduce bird-strike. The efficacy of laser for reducing wild bird numbers in and around free-range poultry areas has however not been investigated. During the autumn–winter, wild bird visits to the free-range area of a layer farm was surveilled by video-camera for a month without laser, followed by a month with laser. The automated laser (Class-III B qualification) was operated in two separate areas (i) within the poultry free-range area that directly bordered the poultry barn between 5:00 p.m. and 10:00 a.m. when poultry were absent (free-range study area, size 1.5 ha), an...
2021
Free-range layer farms have a significantly higher risk of introduction of avian influenza viruses (AIV) compared to indoor layer farms. Wild water birds, natural reservoir of AIV, likely play a role in the transmission of AIV to chickens by contaminating the farms’ free-range area. The use of a laser as a repellent device for wild birds has been studied since the 1970s, in particular around airfields as bird-strike prevention, but its use at poultry farms to keep wild birds away from the surroundings of the poultry barn has not been studied. Part (1.5 ha) of the free-range area of a layer farm that directly boarded the poultry barn was equipped with a video-camera recording system. Visits of wild birds to this free-range study area were recorded for a month without and subsequently a month with a Class-III B laser in operation in the winter period. The laser was operated in the free-range study area between 5:00 PM and 10:00 AM, chickens were present in the free-range study area be...
2000
The interior population of double-crested cormorants (Phalacrocorax auritus) continues to increase. As a result, conflicts between human interests and cormorants have intensified. The impacts of nesting, roosting, and migrating cormorants include predation at aquaculture facilities, interspecific competition with rare species including common terns {Sterna hirundo), and impacts to private property. In addition, heightened public and scientific debate regarding cormorant impacts on sportfish has accelerated the need for effective, socially acceptable methods for managing local conflicts. In 1998 and 1999, USDA, APHIS, Wildlife Services; the New York State Department of Environmental Conservation; and USGS, New York Fish and Wildlife Research Cooperative collaborated on a pilot project to investigate prospective methods and strategies for reducing predation of yellow perch (Perca flavescens) and walleye (Stizostedion vitreum) by fall migrating cormorants on Oneida Lake, New York. The goal of the cooperative program was to reduce stopover time, thereby reducing predation on fish stocks by migrating cormorants. A lakewide integrated non-lethal harassment and roost management program was initiated to disperse local and migrating cormorants from September to October each year. A variety of methods were used to manage cormorants including: electronic guards, propane cannons, mylar tape, human effigies, pyrotechnics, and dispersing birds with a boat. Harassment was focused on birds loafing on the water as well as day and night roosting sites (8 day and 2 night roosts). A total of 52,840 cormorants was dispersed (in many cases individual birds were harassed multiple times) using 1,518 pyrotechnics and 649 staff hours on the lake during the 2 years of the program. Surveys documented a 61%-98% reduction of the cormorants population on Oneida Lake compared to mean counts during the same time period from 1995-1997. Estimated total annual fish consumption by cormorants was reduced by 30% in 1998. Some off-site impacts of the program were seen with increased flocks of cormorants documented on nearby lakes.
Laser dispersal of gulls from reservoirs near airports
2007
Gull numbers roosting at two waterbodies close to a military airfield in central England were monitored at dusk and dawn for four weeks during November 2006. Approximately 25,000 and 8,000 gulls were present at each site respectively. Two LEM 50 laser torches ...
Cormorants (Phalacrocorax carbo) are a protected species in the UK and cannot be killed except under the authority of a licence. It is recognised, however, that cormorants can cause serious problems for inland fisheries and fish farms by damaging stocks of fish and by reducing catches by anglers through changes to fish behaviour. There are a number of legal measures, such as fish refuges or deterrents, that fisheries can employ to reduce predation, but these do not always succeed in reducing damage to acceptable levels. Where this is the case, measures that are ordinarily illegal, such as shooting, may be justified. It is Natural England responsibility to assess applications for licenses to permit such measures to be undertaken for the purpose of preventing serious damage to fisheries in England. The total number of cormorants that may be shot under licence each year by English fisheries is limited to ensure that collectively, licensed killing does not lead to a long-term population...