Range & Distribution  |  ID & Biology  |  Hosts & Habitat  |  Impacts  |  Prevention & Control

Background

The giant African land snail (Lissachatina fulica, formerly Achatina fulica) was originally introduced to Hawaii in 1936 and Florida in 1966. Florida’s original eradication campaign took ten years and cost one million dollars. The snail was rediscovered in 2011. Eradication efforts are ongoing (2015).

Giant African land snails are eaten in many countries and sold as canned pet food for skinks, turtles, monitors, and small animals.

Range and Distribution

Giant African land snails are native to East Africa and found in Asia. In the USA, in Southern Florida and Hawaii, the snails are under quarantine. The USDA APHIS (Animal and Plant Health Inspection Service) has established additional regulated areas in Florida (June 2015). The snails are sold and raised as pets in other countries, including those of Europe. While not yet in New York, the giant African land snail, owing to the illegal pet trade, is prohibited in the state.

Identification and Biology

One of the largest terrestrial snails, full-grown adults can reach almost 8 inches (20 cm) long and 5 inches (13 cm) in diameter.  Adult shells are brownish with darker brown lengthwise stripes, have seven to nine whorls including a swollen long body whorl, and covers at least half the length of the snail. Snails have female and male reproductive organs. One mating can result in multiple clutches of eggs over time. Rapid population increases are likely because each snail can produce 1,200 eggs per year.

Hosts and Habitats

The snails are found in many plant habitats and are known to preferentially consume beans, peas, cucumbers, melons, and peanuts.  Also at risk are ornamental plants, tree bark, and even the plaster, stucco, or paint on buildings.

Impacts

Because of their large size, ability to consume over 500 different kinds of plants, and cause damage to plaster and stucco buildings, the giant African land snail is one of the most damaging snails in the world. The snails are also a potential risk to human health because they can carry a parasitic nematode that can cause meningitis.

Prevention and Control

Giant African land snails are able to survive cold temperatures in a semi-hibernation state. They represent a potential threat to New York even though they thrive in tropical/subtropical areas. If a snail shell is larger than two inches (5-6 cm) it is most likely a type of giant snail. Do not handle with bare hands. Importation is prohibited and specimens will be confiscated by customs. Do not purchase as pets or as educational animals through foreign online dealers or local distributors. For safe removal, or if found outdoors or for sale, contact local New York Department of Environmental Conservation, Cornell Cooperative Extension, or USDA offices.

Background │ Origin │ Habitat │ Introduction and Spread │ Impacts │ Identification │ Prevention and Control │ Occurrences

Background

The European starling (Sturnus vulgaris) is native to Europe and then was introduced into other countries around the world including North America. European starlings have a glossy black appearance and are commonly found in large flocks whose flying is synchronized. About 100 starlings were first introduced by Shakespeare enthusiasts in 1890 in Central Park, New York and are now one of the most abundant birds in North America with a population of approximately 200 million. They are found across the entire United States and compete with native species as well as destroy crops.

Origin

European Starlings’ native range is Europe, southwest Asia, and northern Africa.

Habitat

European starlings are well adapted to living in a variety of environments. Starlings are ground foragers that feed on a variety of insects in the soil as well as various seeds and fruits available. They tend to prefer open grasslands or habitats with low tree and shrub cover. During the breeding season, starlings will nest in cavities, such as holes in trees or other protected spaces. Starlings are very well adapted to disturbance and can be found in rural and urban environments.

Introduction and Spread

European starlings were intentionally introduced into the United States in Central Park, New York because those admiring the works of Shakespeare wanted to see all the birds mentioned in his creations represented in North America. One of the contributors to the success of this invasive species is the starlings’ flexibility in habitat selection (Clergeau and Quenot 2006). Starlings are prolific breeders producing on average one to two clutches per year with four to six eggs per clutch for each nesting pair. Eggs are incubated for approximately 12 days before hatching and then it takes about 3 weeks for nestlings to fledge (Linz et al. 2007). Starlings can live for approximately 2-3 years or more.

Impacts

The damage caused by European starlings on the agricultural industry was estimated to be approximately $800 million per year at $5 per hectare (Pimentel et al. 2000). Starlings eat cattle rations and destroy fruit and grain crops. Some starlings may also carry various diseases which may be transmissible to humans, other birds (including poultry), and livestock (Linz et al. 2007).

Due to the flocking nature of starlings and being well adapted in urban settings, roosts near airports have become a large problem. If a plane flies through a large flock of starlings, the birds can get caught in the jet engines causing damage to the aircraft as well as pose a hazard to humans. Additionally, in urban and rural settings, bird may seek shelter in barns and industrial buildings and create a lot of noise and filth which pose health hazards.

Ecologically, starlings may outcompete native cavity-nesting birds for nest sites. While there are no significant results indicating species declines for all native cavity nesters due to starlings, Koenig (2003) did find that certain species, such as native sapsuckers (Sphyrapicus spp.) were negatively impacted by starling presence. Starlings are also frugivores, meaning they feed on the fruits of plants. When fruits pass through the system of a bird after being ingested it may increase the likelihood that those seeds will germinate in some cases. A study done in 2009 found that the digestive system of starlings will increase seed germination after feeding  on invasive autumn olive (Elaeagnus umbellata) and invasive oriental bittersweet (Celastrus orbiculatus) fruit and that the seed stayed inside the starlings long enough for dispersal to occur (LaFleur et al. 2009).

Identification

Starlings look similar to blackbirds and have a short, square tail with a slender, yellow beak.  Their wings are pointed and triangular. The plumage of a European starling is a glossy black with green, purple, blue or bronze iridescence. In the fall, starlings may have a spotty appearance after molting, but the spots on their wing tips wear away by spring. Male and females look similar however, the female may have a slightly duller appearance.  Additionally, in the breeding season the lower mandible of the beak in males will appear blue-gray and pinkish in females. Starlings are noisy birds making many clicks, whistles, rattles, squeaks, and sounds mimicking those from their environment or songs from other birds.

Prevention and Control

To prevent further spread of European starlings, eggs and nests can be destroyed before the nestlings are able to fledge. Sticky polybutene materials may also be placed in roosting sites to deter birds from landing in a specific area. The most common for removing already established flocks of starlings from an area, is to frighten or harass the birds using propane exploders, pyrotechnics, hawk kites, and ultrasonic sounds. However, using these harassing techniques for control produces only temporary results, as the birds may come back once the control methods are stopped or once they are no longer frightened by them. There are chemicals that have been used that stimulate erratic behavior in birds that ingest it, which frightens other birds away and eventually kills the consumer. Other toxic chemicals, or Starlicides can be used which poison the birds and are lethal within 1-3 days, however non-target birds, such as native song birds, hawks and owls may also be affected if they consume the toxicants. Typically, these chemicals are quickly metabolized and are excreted which reduces effects on organisms higher in the food chain that consume the birds (Linz et al. 2003). When using any chemical, remember to read and follow the directions on the label.

Occurrences

European starlings are native to Europe and in parts of Asia and Africa. They were introduced into North America, South Africa, New Zealand, and Australia. Starlings are now found across the United States, in the Bahamas, Central America, Yucatan Peninsula, Puerto Rico, Jamaica, and Cuba.

Biology  |  Impacts  |  Signs of Feral Swine  |  Management  |  Reporting

Introduction

Feral swine (Sus scrofa), also known as feral pig or wild boar, is a designation that can be applied to the introduced Eurasian boar, escaped or released domestic pig, and crossbreeds of the two. Eurasian boars were introduced to North America as early as 1539 as domestic pigs; additional introductions of other wild Eurasian boar races for hunting occurred through the 1800s and 1900s.

New York populations of feral swine have most likely emerged from escaped and abandoned Eurasian boars kept in captivity and at hunting preserves. Feral swine crossbreed readily with domestic pigs, which has resulted in a wide range of coat colors and body shapes. Many look like typical wild boars, while others may be hard to distinguish from domestic pigs.

Known breeding populations of feral swine in NY (2011) include northwest Cortland, southwest Onondaga, and southern Tioga counties. Pennsylvania also has well established populations in 18 or more counties.  Swine may be seen in several Southern Tier border counties with Pennsylvania. Feral hogs have also been observed in a few upstate counties associated with hunting preserves.

Biology

Feral pigs can breed at any time with a gestation of 115 days. A female is sexually mature at 1 year of age. Litter sizes range from 1-8 piglets; sows aggressively protect their young. Due to their hardiness and ability to adapt to a wide range of weather conditions and food sources, feral swine can triple their population in a year.

Sows average 110 pounds and boars 130 pounds, but can reach up to 400 pounds. Their appearance can be spotted, belted, or striped, entirely brown, or domestic-looking. Their razor sharp tusks can be 5 inches long before breaking or wearing down. Swine use their tusks to defend themselves and to establish dominance. In New York, the adults have few predators to control herd size.

Impacts

Feral swine (Sus scrofa) have a list of environmental, agricultural, and human impacts including:

• Tearing up farm and forest land as they root and wallow, destroying acres of agricultural land and crops in just a few days.
• Carrying diseases transmittable to domestic pigs and humans, including swine brucellosis, pseudo-rabies, trichinosis and leptospirosis.
• Competing with wildlife for food.
• Fouling water supplies.
• Feeding on fawns, ground-nesting birds and reptiles, and even young livestock.
• Destroying wildlife habitat and sensitive natural areas.
• Contributing to erosion and water quality issues.
• Serving as a highway hazard; swine eyes do not reflect in light at night.
• Displaying aggressiveness toward humans with the potential to cause harm.

Signs of Feral Swine

Feral swine are nocturnal; rooting and wallowing in fields and forests, eating crops and hunting. They can decimate acres of fields and gardens every night. Their rooting furrows, 2 to 8” deep, leave a “plowed” look to the landscape.

Their tracks and impressions of their coarse hair can be seen at wallowing holes, creeks, and mud holes. After wallowing, which can destroy habitat, they often rub the mud onto nearby trees. Swine tracks are similar to deer tracks, but more rounded. Swine scat can resemble deer, dog, and human scat.

Management

It is illegal in New York to hunt, trap or take any free-ranging Eurasian boar. This law was passed to discourage the illegal release of boars for hunting. Illegal release is the primary way feral swine are expanding across the US. “Free-ranging” is defined as any Eurasian boar that is not lawfully possessed within a completely enclosed or fenced facility from which the animal cannot escape to the wild. (Environmental Conservation Law Section 180.12, Eurasian boar, April 2014).

Feral swine may be excluded from gardens and domestic hog pens with very heavy duty fencing, but since they can burrow, fencing should be monitored. Domestic swine should be securely enclosed.

Shooting can be used to remove one or two feral hogs, but trapping is recommended for removing family groups. Specially-designed corral traps with heavy metal fencing and mechanical doors are needed to capture free-ranging swine.

Reporting

If you see, shoot, or trap feral swine please report it to your regional NYS DEC Wildlife office http://www.dec.ny.gov/about/50230.html. It is important that natural resource managers know where the swine are.

Feral swine are a threat to New York’s landscape and agriculture. They can cause an immense amount of damage in a short period of time and can transmit disease. Please do not intentionally release swine into the wild for hunting and keep an eye out for escaped domestic pigs. Eradication of feral swine is important.