The Honking Overhead Signals Spring
and
Wildlife Problems
Jim Sellmer, Ornamental Horticulture Extension Specialist

The honking flock of Canada geese overhead brings a sigh of amazement in their numbers and an internal recognition that spring truly is approaching. In several weeks we will see nesting pairs of geese judiciously building nests and ganders aggressively protecting their expectant mates.

A few geese in an area provide a source of wonder and delight for small children and adults. In many areas of the country, nonmigrating Canada goose and duck populations are increasing dramatically. These birds require fresh water for resting and nesting and tender young grass and other succulent vegetation for food. The plentiful, well-manicured lawns of residential neighborhoods, corporate business areas, parks, airports, community gardens, and golf courses are providing excellent habitats for these birds. Geese are particularly opportunistic and can easily become accustomed to people and residential areas.

Although most people find a few birds acceptable, problems quickly develop as bird numbers increase. These problems include overgrazing of grass and ornamental plants; accumulation of droppings and feathers; attacks on humans by aggressive birds; and the fouling of reservoirs, swimming areas, beaches, docks, lawns, and golf courses.

The dramatic recovery of the "Giant" Canada goose from a perceived extinction in the mid 1900's has resulted in an increase in complaints especially in urban areas. The "Giant" Canada goose differs from the autumn and spring migrating "Interior" Canada goose. The "Interior" Canada goose flies through the upper US from Canada to overwintering grounds in the southern US whereas the "Giant" goose is a local nesting goose that has a limited migration. The giant Canada goose weighs-in six to nine pounds heavier than its migrating relative and has adapted very well to urban environments. Municipal parks, zoos, and large corporate campuses with ponds and open mown grassy areas are the most attractive nesting sites for the giant goose.

For more information on the biology of the Canada goose see the Pennsylvania Conservation and Natural Resources Dept. Website at http://www.state.pa.us/PA_Exec/PGC/pubs/w_notes/c_goose.htm.

What can be done to control the movement and damage caused by geese? First, it is important to recognize that the Canada goose is considered an international resource by both the United States and Canada. This designation means that there are strict rules on the hunting and destruction of these birds. Much of their recovery from extinction has been due to a successful and intensive management partnership between state and federal agencies under the terms of the Migratory Bird Treaty Act of 1918.

Once geese have become established on your pond or open grassy area, it may be difficult to get any long-term relief. A good management program tends to be a maintenance activity rather than a quick fix. Some suggestions for managing the geese nesting on your property include:

1. Identify all of the attractants for geese in the immediate area and eliminate or limit their attractiveness. Geese attractive nuisances include:

   Ponds
   Water is attractive to geese. Limit the goose's access to the pond through the installation of overhead grid wires. If your pond has an aerator, turn it off in the winter and allow your pond to freeze. Open water is extremely attractive in the winter when most ponds are frozen.

   Vegetation
   Geese are grazers. They love the tender new growth of well-manicured grass. You can replant heavily goosed grazed areas with ground covers, native grasses or a variety of landscape plants other than turf. A Master Gardener volunteering at a zoo in Racine, Wisconsin observed that geese do not graze aromatic plants like Perovskia, Mentha, and Monarda. In addition, the resident geese also spared the daylilies, sedum, and Callimogrostis. In contrast, the voracious geese grazed and collected nesting materials from the prairie plants (ex. Blue oat grass), blue fescue, and the hostas from the newly planted zoo gardens.

   Nesting Structures
   If goose nesting platforms have been installed in the past, they must be removed. You may also remove any old, abandoned goose nests. Check with your local DCNR wildlife specialist before tampering with nests. Permits are often required before tampering with active nests with eggs or young in them.

   Other Food Sources
   If you have been feeding the geese, this must stop if you want to geese leave.

2. Geese prefer areas with easy access to food, water and nesting sites. Barriers can be effective in deterring and discouraging your resident population.

   Fencing
   Either temporary plastic fencing or more permanent fencing installed around the perimeter of your pond can be affective in containing geese. Temporary fencing along the shoreline with monofilament fishing line strung between fiberglass or wooden poles have been affective. The monofilament fencing should be 24 inches tall with several strands of monofilament fishing line. Place the first strand of line four inches above the ground followed by additional strands at four inch increments up to the 24 inch height. This type of fencing is useful during the nesting season of May through August when the geese are generally flightless and busy with young. After August, the geese can fly and the fencing becomes ineffective.

   Rip Rap Stone Around Pond Edge
   This large stone is most affective in a two to three foot width around the shoreline. The geese and their young have difficulty traversing the rough stone.

   Vegetation Barriers
   A dense row of thorny shrubs can deter a landlocked flock of geese during the nesting season. A thick and dense shrub row is your best option. Useful shrubs include: Berberis koreana (Korean barberry), B. thunbergii (Japanese Barberry), Rosa rugosa (Rugosa rose), R. setigera (Prairie rose) and R. virginiana (Virginia rose). Tall trees and shrubs planted in large open lawn areas can reduce the openness and attractiveness of these areas to geese looking for nesting and grazing sites.

   Visual Barriers
   Three feet high temporary fences made of one or two strands of string tied with brightly colored (hunter orange) or Mylar silver streamers (two to three feet long and five inches wide) have occasionally provided temporary relief from migratory geese. Visual barriers are affective in areas where the migrant geese have not landed. Visual barriers are most affective in combination with noise harassment techniques. Visual barriers are rarely affective with resident geese populations.

3. Repelling the geese and preventing them from nesting in an area through harassment is another option. Harassment is based on the principle of punishment and reward. The birds are harassed (punished) when they attempt to land on the pond or grassy area. Harassment stops (their reward) when they fly away. Harassment requires that you monitor the geese to determine their arrival time. Your goal is to never let them land on your property. If the geese are permanent residents of you property, then you must harass them into flight and then prevent them from landing again. There are three options for harassment or repelling of geese:

   Noise Harassment
   has proven affective in moving geese out of an area when implemented correctly. Hand-held pyrotechnic devices have been most affective and the easiest devices to control. Before using pyrotechnic devices consult with your local police department and conservation officer for permission and local limitations for such devices.

   Visual Harassment
   with plastic owls and snakes have not been successful in moving geese off property. Tethered metallic balloons have shown limited success.

   Chemical Repellents
   for geese based on taste aversion have shown some effectiveness in preventing grazing on turf. Methyl anthranilate is a registered chemical goose repellent. This repellent has not prevented geese from walking through an area or from leaving droppings in an area.

The most successful goose management programs incorporate multiple methods. The combined effects of two or more of the above techniques will provide much more satisfactory result than relying on one method. You may obtain more information about managing waterfowl and the wildlife services of USDA Animal Damage Control Office through their website at http://www.aphis.usda.gov/oa/pubs/wswfowl.html. You can call the ADC Operational Support staff at (301) 734-5149 to find the ADC office nearest you.

Solving the urban goose problems that are very apparent to landscape managers, superintendents, nursery managers, homeowners, and volunteers during the summer nesting season will not be easy. Retaliation toward these birds, their nests, eggs or young due to frustration is not the answer. Remember these are locally and federally protected species that are managed to assure their survival. Malicious acts are punishable by law. Instead of letting the frustration get the best of you; choose logical and useful management strategies.

The identification of goose tolerant or repellent plants for the garden and landscape require more attention. If you have a goose problem and you observe specific plants that remain unmolested or seem to repel the geese over several years, report it to your local cooperative extension agent. The more we learn about plants that are unattractive to geese the better we can plan our landscapes.

Prevent Deer Browsing:
Avoid Plants Preferred by Deer and
Choose Plants Undesired by Deer
Jim Sellmer, Ornamental Horticulture Extension Specialist

Every year after the growing season is over horticulturist ask whether there is a treatment or technique for preventing deer damage to our favorite trees, shrubs, perennial and annual flowers and grasses. We look to the numerous topical repellents for inhibiting deer feeding including: thiram, hot sauces, ammonium soaps, putrefied animal byproducts, bags of hair or your favorite home remedy. Alas, we learn over time that these materials work for a brief period but either the animals become tolerant or the repellents require repeated applications due to weathering. Other more complex options are available including governmentally administered deer damage abatement programs, scare devices, electrified fences, and dogs within radio controlled enclosures (invisible fencing).

Probably the simplest approach to avoid deer damage to garden plants is to consider those plants which deer tend not to browse. Being observant of our landscapes and the actions of the deer that regularly browse can help you to identify plants that are undesirable to the deer. Remember, plants that are recommended as non-attractive to deer during average years may be attractive in years with severe winters and limited natural browse sources.

The following lists of deer preferences are from two sources: by local residents surrounding the Schlitz Audobon Center located in Milwaukee, WI and W.S. Feeney, WI Wildlife Research Progress Report, Vol. v (1), January 1946. The list provides plants preferred by deer for those of you who might want to promote deer activity in your property and non-preferred plants for those of you wishing to reduce deer impact. This is not a complete list and there is a chance that the list will grow over time and with your observations.

*Note: table information was taken from the Audobon Society Observations
& Wisconsin Wildlife Research--Progress Reports, Vol. V (1), January, 1946.

Information provided by Rob Berghage and Jim Sellmer Penn State Department of Horticulture, Ornamental Horticulture Extension Specialist, 103 Tyson Building, University Park, PA 16802, (814) 863-2571

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