Resident Canada Geese Research Articles

Factors influencing nest survival in resident Canada geese

ABSTRACTOverpopulation of Canada goose (Branta canadensis) that make up the Atlantic Flyway Resident Population (AFRP) in New Jersey led to the implementation of a management program that includes hunter harvest, culling programs, and efforts to reduce recruitment through nest destruction. We investigated clutch size, hatchability, and nest survival of Canada goose nests in the AFRP in New Jersey during 1985–1989, 1995–1997, and 2009–2010, and identified ecological, temporal, and spatial variables associated with nest survival to better understand the factors influencing population growth. Mean (±SE) clutch size was 4.86 eggs (±0.04), and mean hatchability of all eggs was 0.61 ± 0.04 across the study. Mean hatchability in 2009–2010 was significantly lower than in the 1980s and 1990s, whereas we did not detect any significant differences in mean clutch size across the decades. Nest survival decreased across the decades, with survival probabilities ranging from 0.68 ± 0.03 in 1988 to 0.45 ± 0.02 in 2010, likely related to reproductive control programs. Nest survival was influenced by date within the nesting season, decade, precipitation, and extreme high temperature. Further, nest survival was associated with commercial‐industrial, agricultural, and urban residential land use at a site level (0.25 km), and natural and urban residential land use at a landscape level (2.25 km and 0.75 km, respectively). Commercial land use (e.g., corporate parks and golf courses) offers favorable Canada goose nesting habitat at the site level, with manicured lawns, man‐made ponds, and decreased predator habitat (e.g., dense tree, shrub cover). We recommend targeting population management efforts in commercial, industrial, and urban residential areas these land uses were associated with increased nest survival. © 2016 The Wildlife Society.

A population model for management of Atlantic flyway resident population Canada geese

ABSTRACTHighly abundant resident Canada geese (Branta canadensis) cause property damage throughout their range. Effective reduction and management of these populations requires knowledge of their population dynamics and responses to management actions. We used data from New Jersey, USA, and other resident Canada goose populations to produce stage‐structured matrix models for resident Canada geese from both urban and rural landscapes. We ran stochastic simulations to assess 3 management activities for Atlantic Flyway Resident Population Canada geese: harvest, nest treatment, and cull. Unrealistic harvest rates, in excess of 10% for urban geese, would be needed to reduce the urban population to target levels within 10 years in the absence of other management activities. Nest treatment to prevent hatching is less controversial than culling adults, but as many as 62% of eggs in urban areas would need to be treated annually to sufficiently reduce the mean stochastic population growth rate. Cull would be the most effective way to achieve the population goal, but current cull rates are insufficient to reduce the urban population. Although reduction of urban geese was a challenge, current management activities in rural populations appeared to be sufficient to reduce populations. We also provide a simple spreadsheet tool for managers who want to explore management options for other resident Canada goose populations by inserting relevant vital rate estimates for their populations and manipulating management activities. © 2016 The Wildlife Society.

Evaluation of resident Canada goose movements to reduce the risk of goose‐aircraft collisions at suburban airports

ABSTRACTResident (non‐migratory) Canada goose (Branta canadensis) populations in suburban environments pose risks to human health and safety. Specifically, the relatively large size and gregarious behavior of geese combined with an overlap in aircraft flight space pose substantial risk of property damage and human fatalities from goose‐aircraft collisions. We estimated home range and core use areas of resident Canada geese and evaluated goose movements to better define the risk of goose‐aircraft collisions around Piedmont Triad International Airport in Greensboro, North Carolina, USA. We placed satellite transmitters on 16 of 763 neck‐ and leg‐banded geese to identify and track individuals over an 18‐month study period. The frequency of satellite‐tagged goose movements peaked daily within the first 2 hours after sunrise (28.1%) and again near sunset (27.2%). All in‐flight goose movements occurred ≤64 m above ground level. Geese flying at these altitudes posed a risk to aircraft in the take‐off and landing phases of flight. For all in‐flight movements, the number of movements per day was 0.13 during the molt (1 Jun–15 Jul), 0.42 during early post‐molt 2008 (16 Jul–31 Oct), 0.36 during late post‐molt (1 Nov–31 Jan), 0.58 during breeding/nesting (1 Feb–31 May), and 0.58 during the early post‐molt 2009. Satellite‐tagged geese traveled a mean distance ranging from 2.0 km (SE = 0.3) to 4.9 km (SE = 0.4) per day, depending on sex and season, which supports the need for intensive goose management within a minimum distance of 8 km from airports. Mean fixed 95% kernel home range and 50% core use area were 991.8 ha (SE = 241.1) and 120.4 ha (SE = 24.6), respectively. Additionally, we monitored site recolonization of nuisance geese after the controlled removal of 60 resident geese from 1 site, which eliminated 24.2% of those initially banded at the site in 2008, but other geese began to recolonize the site within 27 days. Rapid recolonization of the removal site suggests that lethal removal should be conducted at all molt locations within a minimum distance of 8 km of suburban airports and any additional removal or management resources should be applied to greater distances to prevent recolonization of these sites by geese in close proximity to the removal site. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Integrated damage management reduces grazing of wild rice by resident Canada geese in New Jersey

ABSTRACTTidal freshwater marshes of the Maurice River, New Jersey, USA, have been long renowned for robust stands of wild rice (Zizania aquatica). During the 1990s, these marshes experienced an apparent decline in wild rice. During 2000–2002, I used paired fenced exclosures and open control plots to measure herbivory by the Atlantic Flyway Resident Population of Canada geese (Branta canadensis) on wild rice and response of rice to an integrated damage management program (IDMP). The IDMP consisted of rendering goose nests unhatchable, shooting, and culling molting geese. The IDMP reduced the number of goslings by 60% during the first year and essentially eliminated recruitment during the second year. Prior to the IDMP, grazing by geese reduced the density of rice by 78% and the height of plants surviving grazing by 17%. With implementation of an IDMP, rice density between exclosures and control plots did not differ. Wetland managers should consider the grazing impacts that resident population Canada geese can incur on native plant communities and develop a plan for mitigating that damage. © 2014 The Wildlife Society.

THE POLITICAL AND SOCIAL BARRIERS FOR CONTRACEPTION IN PEST BIRDS: A CASE STUDY OF OVOCONTROL® (NICARBAZIN)

In a joint program, Innolytics and the U.S. Department of Agriculture/Animal and Plant Health Inspection Service National Wildlife Research Center collaborated in the development of nicarbazin as an avian contraceptive, initially for resident Canada geese and subsequently for feral pigeons. Unfortunately, the introduction of the original goose product in 2005 was a commercial failure. Political and social barriers effectively thwarted attempts to establish the new technology with any meaningful market success. Although the market adoption of the pigeon contraceptive has been less difficult, the product still encounters significant social and political obstacles and opposition. Given the focus on instant results and gratification, the introduction of contraceptive technology for birds has been challenging and broad market acceptance remains elusive. Nevertheless, especially for short-lived and rapidly reproducing species, customers continue to replace outdated or ineffective techniques with the safer and more effective contraceptive tool.

Ten years of resident Canada goose damage management in a New Jersey tidal freshwater wetland

ABSTRACTIntensive grazing by Atlantic Flyway Resident Population Canada geese (Branta canadensis) has been shown to dramatically reduce wild rice (Zizania aquatica) abundance in tidal freshwater marshes in the Mid‐Atlantic Region of the United States. From 2001 to 2010, I implemented an integrated damage management program (IDMP) during spring to abate Canada goose herbivory to wild rice in tidal freshwater marshes of the Maurice River, New Jersey, USA. The IDMP consisted of shooting, rendering goose nests unhatchable, and euthanizing molting geese. With implementation of an IDMP, the number of nests on the study area declined 70% over 10 years and the number of geese declined over time. Consequently, the amount of IDMP effort needed to sustain rice was reduced. Because the study area was a key nesting site for ospreys (Pandion haliaetus), which are state‐threatened species, there was concern that disturbance from IDMP activities could have a negative impact on osprey nesting or recruitment. The mean annual number of nesting ospreys doubled and the mean number of young fledged/nest was similar between years prior to and during implementation of the IDMP, suggesting that the IDMP did not have a negative impact on ospreys. Wetland managers should consider damage from excessive herbivory caused by non‐native, breeding waterfowl, such as resident Canada geese or mute swans (Cygnus olor), in their suite of wetland mitigation strategies. © 2013 The Wildlife Society.

CHARACTERIZATION OF CAMPYLOBACTER FROM RESIDENT CANADA GEESE IN AN URBAN ENVIRONMENT

Waterfowl are natural reservoirs for zoonotic pathogens, and abundant resident (nonmigratory) Canada Geese (Branta canadensis) in urban and suburban environments pose the potential for transmission of Campylobacter through human contact with fecal deposits and contaminated water. In June 2008 and July 2009, we collected 318 fecal samples from resident Canada Geese at 21 locations in and around Greensboro, North Carolina, to test for Campylobacter. All campylobacter species detected were C. jejuni isolates, and prevalences in 2008 and 2009 were 5.0% and 16.0%, respectively. Prevalence of C. jejuni-positive sampling sites was 21% (3/14) and 40% (6/15) in 2008 and 2009, respectively. All C. jejuni isolates were susceptible to a panel of six antimicrobial agents (tetracycline, streptomycin, erythromycin, kanamycin, nalidixic acid, and ciprofloxacin). We used pulsed-field gel electrophoresis and fla-typing to identify several strain types among these isolates. Multilocus sequence typing of representative isolates revealed six sequence types, of which two (ST-3708 and ST-4368) were new, two (ST-702 and ST-4080) had been detected previously among C. jejuni from geese, and two (ST-991 and ST-4071) were first reported in C. jejuni from an environmental water source and a human illness, respectively. These results indicate a diverse population of antibiotic-susceptible C. jejuni in resident Canada Geese in and around Greensboro, North Carolina, and suggest a need for additional assessment of the public health risk associated with resident Canada Geese in urban and suburban areas.

Evaluation of a clutch‐containment method during hatch in geese: Using resident Canada geese as an example

AbstractDisruption associated with nest visits during the hatch period of waterfowl can cause partial abandonment of hatchlings, potentially causing bias in the survival of marked birds. We evaluated the use of a mesh clutch‐containment bag to capture and mark entire broods of 151 resident Canada goose (Branta canadensis) nests, prior to hatch, while minimizing observer‐caused disruption during brooding. The study was conducted in New Jersey, USA, from April to June 2010. No differences were found in hatch success or the number of hatchlings marked between contained clutches and the control group. Although this technique was not beneficial in studying gosling survival in temperate nesting populations, it may be effective in sub‐Arctic nesting conditions where nest visits are conducted using a more invasive approach such as a helicopter. © 2012 The Wildlife Society.

The Effect of Experimental Removal of Single Breeding Pairs of Resident Canada Geese

Author(s): Lynch, Ryan P.; D’Angelo, Gino J. | Abstract: Resident Canada geese cause substantial economic losses to agriculture and personal property and compromise air traffic safety throughout the U.S. Destroying eggs of Canada geese nesting in the contiguous U.S. is a primary component of the integrated management regime to reduce damage caused by the species. This requires regular searches to destroy eggs throughout nesting season, which may be laborious and costly. Much of the breeding by resident Canada geese occurs on small ponds (≤5 acres). Anecdotal observations suggested that social pressure among breeding pairs of Canada geese typically dictates that only one aggressive breeding pair establishes a territory on small ponds. Using this logic, managers allow a single nesting pair on small ponds and destroy their eggs, while deriving the perceived benefits of the sentinel geese excluding other nesting geese. However, a single pair of geese may also cause damage, decimating plants and depositing accumulations of feces in the localized area. We hypothesized that removal of single nesting pairs of Canada geese on small ponds after the onset of breeding activity would result in a void of geese for the remainder of the reproductive season, thus providing an alternate lower-cost management strategy. We further hypothesized that if the male goose was not removed, he would continue to defend the territory, excluding other nesting geese. Our study was conducted on 22 independent sites with small ponds in Bucks County, southeastern Pennsylvania. Each site held historically one nesting pair of Canada geese. To test our hypotheses, breeding pairs of Canada geese were assigned to one of three experimental groups: 1) control neither female nor male goose was removed, the eggs were treated under normal protocols to prevent hatching, and the nest and eggs were removed after the 28-day incubation period; 2) after nest initiation, only the female goose was removed, and the nest and eggs were removed; and 3) both the female and male goose were removed and the nest and eggs were removed. We determined that targeted removal of a nesting pair or only the female of a nesting pair of Canada geese could be effective in eliminating breeding on a small pond for the entire nesting season. Likewise, the traditional approach of allowing a single aggressive nesting pair on small ponds reliably excluded additional nesting pairs.

Effects of Mowing on Anthraquinone for Deterrence of Canada Geese

ABSTRACT Anthraquinone (AQ)‐based repellents have been shown to reduce Canada goose (Branta canadensis) use of turfgrass; however, impacts of frequent mowing on efficacy of AQ have not been studied. Our objective was to determine efficacy and longevity of a rain‐fast AQ‐based avian repellent, FlightControl® PLUS (FCP), as a deterrent of free‐ranging resident Canada geese under 2 mowing frequencies. We conducted the study at 8 sites in the Triangle region (Raleigh, Durham, and Chapel Hill) of North Carolina, USA. We arranged our experiment in a randomized complete block design, with each of 8 sites containing 4 0.1‐ha treatment combinations: 1) treated with FCP and mowed every 4 days (T4), 2) treated with FCP and mowed every 8 days (T8), 3) untreated and mowed every 4 days, and 4) untreated and mowed every 8 days. We conducted 4 37‐day field sessions (Jun‐Jul 2007, Sep‐Oct 2007, Jun‐Jul 2008, and Sep‐Oct 2008), representing the summer molting phase and the full‐plumage phase. Resident goose use (measured by daily no. of droppings) was 41–70% lower on treated plots than on untreated plots, but use was similar between T4 and T8. Average FCP coverage on grass blades decreased in coverage from approximately 95% to 10% over the 30‐day posttreatment phase. Results indicate that resident Canada goose use of FCP‐treated turfgrass areas was lower than untreated areas even when chemical coverage on grass was 10%. Further, mowing frequency did not have a clear impact on the efficacy of FCP as a Canada goose repellent.

Demographic Parameters of Rural and Urban Adult Resident Canada Geese in Georgia

ABSTRACT In many urban metropolitan areas, resident Canada goose (Branta canadensis) populations have grown to nuisance levels in spite of increasing harvest opportunity. To document differences in demographic parameters between urban and rural geese, I estimated probabilities of survival, recapture, recovery, and fidelity for adult resident Canada geese between 2001 and 2006 using banding, live recapture, and dead recovery data from 2 distinct banding locations in Georgia, USA. Adult survival rates were higher for urban geese (0.958, SE = 0.020) than for rural geese (0.682, SE = 0.049). Using estimated recovery probabilities of 0.505 (SE = 0.107) for urban and 0.463 (SE = 0.045) for rural geese, along with current estimates of crippling loss and reporting rate, the estimated mean harvest rate for urban geese was 0.029 (SE = 0.006) and for rural geese was 0.202 (SE = 0.020). Fidelity rates were similar between urban (0.730, SE = 0.033) and rural geese (0.713, SE = 0.069). This information suggests that urban segments of the Canada goose population have substantially higher survival than rural geese and are harvested at a very low rate, and that liberalizing hunting regulations may have little impact on Georgia's urban goose population. Wildlife managers may need to consider options other than sport hunting to control nuisance goose populations in urban areas.

Canada Goose Weed Dispersal and Nutrient Loading in Turfgrass Systems

High populations of Canada geese (Branta canadensis L.) can lead to feces accumulation in areas adjacent to surface waters, creating concern about aquatic eutrophication. Further, turf managers and livestock farmers work to keep their facilities free of noxious or toxic weeds that geese potentially disperse. We investigated the prevalence of viable seeds and nitrogen and phosphorus content in resident Canada goose droppings. During spring, summer, and fall of 2008, we collected 127 fresh individual droppings which were placed in seedling trays within an irrigated greenhouse and allowed 30 days for weed seed to germinate. Trays were cold stratified for 30 days and returned to the greenhouse for an additional 30 days. Also, during summer and fall of 2007 and 2008, we tested 304 fecal samples from 8 sites for total Kjeldahl nitrogen (TKN) and total phosphorus (TP). Out of 127 droppings planted, 4 plants germinated (3.1%): Pennsylvania smartweed (Polygonum pennsylvanicum L.), annual bluegrass (Poa annua L.), and 2 Kyllinga spp. The average amounts of TKN and TP in fecal samples were 24.2 mg/g (range = 12.6 to 55.7) and 3.6 mg/g (range = 1.4 to 8.3) of dry matter, respectively. The results indicate that Canada geese in suburban and urban areas are not frequent vectors of viable seeds, but do have potential to contribute nutrients to adjacent surface waters.

Evaluation of an Integrated Non-Lethal Canada Goose Management Program in New York (2004 - 2006)

New York State has an estimated population of 249,702 resident Canada geese. Human-goose conflicts are increasing, including unacceptable accumulation of goose feces in public parks, overgrazing of landscaped lawns, noise, and aggressive behavior of individual geese. An integrated Canada goose management program was conducted and evaluated at 8 sites in Orange County, New York from 2004 to 2006. The program, conducted from March through November each year, consisted of egg oiling (300-470 eggs oiled a year), hazing to reduce local goose populations using multiple techniques, public outreach/education, and program monitoring. The monitoring component included goose movement and population surveys using neck-collared geese and standardized fecal counts, at both managed and unmanaged sites. We monitored 3 unmanaged (control) sites to provide a comparison. We conducted fecal surveys, as an indirect method for potentially estimating site-specific goose populations and associated reduction in damage. The number of droppings counted, when standardized to droppings per foot per day, decreased at treated sites (2004, 0.16; 2005, 0.12; 2006, 0.05) but did not differ at unmanaged sites, indicating a sustained population reduction on site during the project. In addition, the mean number of geese observed at treated sites decreased each year (2004, 77; 2005, 19; 2006, 11) while the mean number at unmanaged sites did not differ. The alternate location of the majority of dispersed geese is unknown, although monitoring of marked birds indicates that many birds moved only short distances (<2 km). The implementation of an integrated non-lethal goose damage management program over 3 years reduced the number of Canada geese at specific locations and minimized local conflicts. The widespread adoption of this type of program could reduce human- Canada goose conflicts across a larger landscape but will require extensive coordination of local projects, a public involvement process, and an intensive, long-term commitment of resources.

Nicarbazin bait reduces reproduction by pigeons (Columba livia)

Development of effective methods for reducing populations of overabundant nuisance bird species continues to challenge wildlife biologists. Reproductive inhibition, although conceptually pleasing, has been difficult to implement because of the lack of a safe, approved avian contraceptive. Recently, however, nicarbazin received regulatory approval in the United States for use as a bait to decrease hatchability of resident Canada goose (Branta canadensis) and feral pigeon (Columba livia) eggs. In anticipation of the feral pigeon registration, we evaluated efficacy by exposing captive pairs of nesting pigeons to nicarbazin bait for 4 h daily. Egg production was unaffected, but only 9 of 22 eggs hatched, a 59% reduction from pre-treatment when each of the 11 test pairs produced 2 nestlings. In the recovery phase, when treated bait was removed, the 11 pairs produced 18 nestlings. All nestlings produced during the study appeared healthy and normal, and there was no mortality among the adult pairs. Nicarbazin is an effective and safe means of reducing hatchability of feral pigeon eggs that can be used within an integrated management plan to reduce feral pigeon populations.

Herbivory by Resident Geese: The Loss and Recovery of Wild Rice Along the Tidal Patuxent River

Abstract: Well known for a fall spectacle of maturing wild rice (Zizania aquatica) and migrant waterbirds, the tidal freshwater marshes of the Patuxent River, Maryland, USA, experienced a major decline in wild rice during the 1990s. We conducted experiments in 1999 and 2000 with fenced exclosures and discovered herbivory by resident Canada geese (Branta canadensis). Grazing by geese eliminated rice outside exclosures, whereas protected plants achieved greater size, density, and produced more panicles than rice occurring in natural stands. The observed loss of rice on the Patuxent River reflects both the sensitivity of this annual plant to herbivory and the destructive nature of an overabundance of resident geese on natural marsh vegetation. Recovery of rice followed 2 management actions: hunting removal of approximately 1,700 geese during a 4‐year period and reestablishment of rice through a large‐scale fencing and planting program.

Nicarbazin OvoControl G Bait Reduces Hatchability of Eggs Laid by Resident Canada Geese in Oregon

Abstract: Expanding populations of resident Canada geese (Branta canadensis) are resulting in increased conflicts with humans. Nonlethal and humane means are needed for managing Canada goose flocks at a variety of sites, including golf courses, industrial parks, government sites, and city parks. Decreased egg production and hatching are side effects of nicarbazin, a veterinary drug used to treat coccidiosis in chickens. Capitalizing on these effects, we developed nicarbazin as a reproductive inhibitor for Canada geese and conducted a field efficacy study. We recruited study sites in 2002 and 2003. Following laboratory testing, we conducted a field efficacy trial of nicarbazin for reducing the hatchability of Canada goose eggs in spring 2004 in Oregon, USA. The study began in February 2004 at 10 sites in Oregon, with 2 control and 3 treated sites on each side of the Cascades. We fed bait daily to resident Canada geese for approximately 6 weeks. We located and monitored nests until hatching or ≥5 days beyond the expected hatching date to determine hatchability. We completed data collection in May 2004. Geese consumed 8,000 kg of bait, with 5,100 kg of OvoControl G® (Innolytics, LLC, Rancho Santa Fe, CA) 2,500‐ppm nicarbazin bait consumed among 6 treated sites and 2,900 kg of untreated bait consumed among 4 control sites. We monitored 63 nests at treated sites and 46 nests at control sites to determine hatching success of eggs. There was a 62% reduction in the percentage of nests with 100% hatchability at treated sites as compared to controls. There was a 93% increase in the percentage of nests at treated sites with 0% hatchability as compared to nests with no eggs hatching at control sites. Hatchability from treated sites versus control sites was reduced 36% (F = 5.72, P = 0.0622). We submitted results from this study to support Environmental Protection Agency registration of nicarbazin as a reproductive inhibitor for use in Canada geese. We have shown that treatment of resident Canada geese with OvoControl G 2,500‐ppm nicarbazin bait by licensed, trained applicators immediately prior to and during the breeding season can reduce hatchability of eggs laid by treated geese, thereby reducing recruitment of goslings into problem resident Canada goose populations.

Restoring complex vegetation in urban settings: The case of tidal freshwater marshes

Tidal freshwater marshes have diverse plant communities that vary spatially and temporally due to hydrology, animal activity, and other factors. Development of urban centers along rivers of the U.S. Atlantic coast has reduced the historic extent and quality of these and other coastal wetlands. Because the vegetation of these wetlands is more complex than that of salt and brackish marshes (where restoration of vegetation typical of natural systems has sometimes been successful), restoration of tidal freshwater marsh vegetation is likely to be more difficult, particularly in urban areas. Watershed urbanization alters hydrology, sediment load, propagule availability and composition, nutrient status, and other variables that together create an environment different from that of wetlands in less developed areas, possibly precluding restoration of typical marsh vegetation. Tidal freshwater wetlands were historically extensive along the Anacostia River in Washington, DC, but most of these were lost due to filling, dredging, or hydrologic alteration. Over the last decade, the U.S. Army Corps of Engineers has implemented projects designed to restore tidal freshwater wetlands along the Anacostia, which involved increasing elevation with dredged river sediment and planting native vegetation. To illustrate some of the mechanisms affecting vegetation development in restored tidal freshwater marshes in urban areas, I present a case study on one of these wetlands, Kingman Marsh, that also includes research at another restored wetland and two natural reference sites. Studies by my research groups indicate that the restored wetlands undergo essentially a planting-modified process of primary succession. Low densities of seeds are initially present in the substrate, and prolific seed dispersal into the restored sites results in high initial plant diversity comprised of plantings and ruderal (i.e. weedy) natives and exotics. Seed banks develop rapidly at the restored sites, probably due to colonization and early reproduction by ruderal species. Hydrology and disturbance by non-native animals (including resident Canada goose) are important variables controlling establishment of vegetation in these systems. Recent literature and the case study indicate that the environmental conditions of urban settings impose constraints in restored wetlands that result in plant communities more like those of urban natural wetlands than those of wetlands in less urbanized watersheds. This suggests that rather than design wetland restoration projects with the goal of creating “pristine” wetland vegetation, restorationists must identify, accept, and if possible capitalize on the ecological constraints of the urban environment in setting achievable and desirable restoration goals.

The effectiveness of a long-term Canada goose relocation program in Nevada

Author(s): Hall, Thomas C.; Groninger, Paige | Abstract: The resident Canada goose (Branta canadensis) population in Truckee Meadows (TM) increased in the 1980s from a few hundred to an estimated 1,200 by 1988. Concern arose after two incidents in which aircraft from Reno/Tahoe International Airport hit resident geese. As a result of a FAA mandate, a multi-agency task force led by USDA APHIS Wildlife Services was developed to address the problem. As a result of a recommendation from the task force, an annual Canada goose round-up with subsequent relocation was started in 1989 and has continued through 2001. Of the 7,954 geese initially captured, 3,081 (39%) were recovered (death, recapture, sighting) at a later date at least once. Of the 11,397 captures (newly banded and recaptured geese), 5,269 were released at the capture site and 6,128 were relocated. In addition, 347 geese were captured and released in TM in 1986-87 for a study conducted by the Nevada Division of Wildlife (NDOW). During the first few years of the program, juveniles and some adults captured in TM were relocated. Since 1997, all geese captured have been relocated. Of the geese released at the capture site prior to 2001, 59.6% of the adults and 40.6% of the juveniles were recovered at least once in TM. Comparatively, only 21.2% of the first-time relocated adults and 3.5% of the relocated juveniles have returned to TM, a significant difference for both (Pl.0001). Second-time released and relocated adults were recovered a third time in TM at 68.5% and 32.8% (Pl.0001). However, adults released or relocated 3 or more times have been recovered similarly in TM at 69.5% and 71.0% (P=.846). Relocated geese are subject to higher hunting mortality by about 8% (Pl.0001); hunting as a management tool appears to have helped reduce the returning population. As a result of the relocation program, the population in TM has declined from a high of about 2,000 to 400 at the same 10 sites. The current population throughout TM is about 800. We conclude that the relocation program has been effective in reducing the Canada goose population in TM, except that relocating geese three or more times is not worthwhile.

Resolving conflicts between people and canada geese: the need for comprehensive management approaches

Author(s): Hadidian, John | Abstract: Canada geese have become established and are now numerous enough in many urban and suburban areas that conflicts with humans have become frequent. Although potential threats to human health are often cited as a justification to manage goose populations, currently available science suggests that this is not a serious issue. This leaves the primary concern as one of aesthetics– people do not like having to deal with what can sometimes be copious amounts of goose droppings. Animal welfare interests have questioned the humaneness of different roundup and killing programs, and advocated non-lethal approaches and egg addling. Both approaches currently are being practiced in a number of different communities without, unfortunately, much being done to systematically monitor or evaluate them. This paper addresses some of the more controversial issues surrounding resident Canada goose management from an animal welfare perspective and touches on some of the different management approaches currently being practiced as examples of the need for better overall coordination and comparison of management approaches.

Egg fertility among vasectomized and non-vasectomized male resident Canada geese at the Wildlife Conservation Park/Bronx Zoo

In 1991, a vasectomy program was initiated at the Wildlife Conservation Park/Bronx Zoo to minimize the population growth of resident Canada geese (Branta canadensis). Sixty-nine males were vasectomized over a 6-year period. From 1994 to 1998, egg fertility was examined in females paired with vasectomized and non-vasectomized geese. Of the 340 eggs laid by females paired with vasectomized males, 12% were fertile. In comparsion, of the 526 eggs laid by females paired with non-vasectomized males, 90% were fertile. The vasectomy procedure was easier to perform on males captured during the breeding season than on those captured during molt owing to the enlarged size of the vas deferens. Where resident Canada goose populations are small and resources available, the implementation of a vasectomy program can be effective in reducing population growth. Zoo Biol 19:35–40, 2000. © 2000 Wiley-Liss, Inc.