Only $2.99/month

Invasive Species- Animals

Terms in this set (66)

(Anoplophora chinensis)
•It is a specific type of beetle that attacks healthy Citrus trees.
-It was first detected in the U.S. in a Washington nursery. (It was found on Maple saplings).
-It is also found throughout Asia and in the Mediterranean sea area.
*Related to the Asian Longhorned Beetle.
•The eggs hatch from april to August in China, and most of them hatch from May to July.
-It usually takes from 1 to 3 weeks for the larvae to hatch from the eggs. Later on in the larval stage, the beetles make tunnels under the bark. (They feed on green sappy sections of the bark in citrus fruit trees.
-The larvae start out by making small tunnels underneath the bark of the tree, and later on are able to make tunnels deeper into the tree.
*It attacks over 100 different types of trees. (Mostly Lime, lemon, orange, and tangor trees).
•The most damaging part of the life cycle of this beetle is the larval stage. In this stage, the tunnels under the bark and later throughout the wood can disrupt the flow of sap through the tree. They also let diseases spread more easily.
-Report it by sending a sample to the State Department of Agriculture.
-Natural predators such as certain types of ants. Certain types of fungi can be pathogenic to these beetles.
-Burning and chipping the plants helps with the larvae problems.
-Putting guards around the trees to help prevent the females from laying their eggs on the tree.
-Injecting insecticides into the base of the tree is good for eradication.
(Neogobius melanostomus)
Round Gobies are bottom-dwelling fish that were introduced to the Great Lakes from central Eurasia via the ballast water of large, ocean-going cargo ships. Native to central Eurasia including the Black Sea and the Caspian Sea. This species was introduced into the St. Clair River and vicinity on the Michigan-Ontario border where several collections were made in 1990 on both the U.S. and the Canadian side.
With their introduction into the Great Lakes, Gobies have created significant economic and ecological impacts. The four areas below explain these impacts.
Food Chain Impacts: Fishery managers have found that Gobies have been able to compete successfully with native, bottom dwelling fish such as sculpins and darters. Fishery managers have found substantial reductions in local populations of sculpins in areas in where gobies have become established. The Goby invasion has impacted the food chain of recreationally important fish such as smallmouth bass and walleye.
Direct Predation: While gobies may compete with sculpins for food or drive them from their preferred habitat and spawning area, laboratory experiments have shown that gobies will eat darters and other small fish. This finding is of concern, because gobies have also been shown to feed on the eggs and fry of lake trout, which has been observed in laboratory experiments. Combine this with the already limited reproduction of the lake trout in the Great Lakes and the potential collapse of an economically significant fishery is possible.
Contaminants Transfer: On the positive side, round gobies eat large quantities of zebra mussels, another invader that is causing an increasingly large number of problems because of its huge reproductive output. As filter feeders, Zebra mussels, consume toxins that are found throughout the Great Lakes. Zebra mussels are an important component of the gobies' diet in their native range; and, in laboratory studies in North America, a single round goby can eat up to 78 zebra mussels a day. However, it is unlikely that gobies alone will have a detectable impact on zebra mussels. The round goby is expected to be one of several species (including ducks, crayfish, diseases, and other fish species) that eventually will reduce the abundance of zebra mussels. The concern about this fact is that Gobies are preyed upon by several sportfish species (e.g., smallmouth and rock bass, walleyes, yellow perch, and brown trout). Because the diet of round gobies consists predominately of zebra mussels, there may be a direct transfer of contaminants from gobies to sport fish, which could increase the health concerns about eating fish.
Nuisance Competition: One of the more annoying impacts of Gobies is their aggressiveness with regard to recreational fishing. These fish aggressively take bait from hooks. Anglers in the Detroit area have reported that, at times, they can catch only gobies when they are fishing for walleye.
In 1990, round gobies were found only in the areas adjacent to the St. Clair River: Lake St. Clair and in the first 2 km of the upper Detroit River. By 1995, they had spread to Duluth-Superior Harbor, in Duluth, Minnesota (Lake Superior), Montrose Harbor north of Chicago (Lake Michigan), and Ashtabula River in Ohio (Lake Eric).
Because the gobies have entered into the Mississippi River drainage, their range will naturally expand beyond the Great Lakes. However, anglers need to learn how to identify Round Gobies and not use it as bait. Preventing this practice will help to reduce the spread of gobies.
Short term benefits of round gobies don't override long term impacts
Zebra Mussel Predator - Round gobies eat large quantities of zebra mussels, another hitchhikers that is causing problems because of its huge reproductive output. Zebra mussels are an important component of the gobies' diet in their native range; and, in laboratory studies in North America, a single round goby can eat up to 78 zebra mussels a day. However, it is unlikely that gobies alone will have a detectable impact on zebra mussels.
Game fish Prey - While gobies are preyed upon by several sport fish species (e.g., smallmouth and rock bass, walleyes, yellow perch, and brown trout), there may be a perception that gobies are beneficial for fishing. However, because their diet consists predominately of zebra mussels, there may be a direct transfer of contaminants from gobies to sport fish, which could ultimately harm humans who consume their catch.
How can I prevent the spread of Round Gobies?
Learn to identify gobies. To enable biologists to track the spread of round gobies, up-to-date information on new sightings is needed. Your assistance is extremely important. If you catch a round goby outside the areas noted on the map indicating goby range, preserve the fish either in alcohol (grocery store rubbing alcohol is fine) or by freezing it. Then contact your state fisheries management agency or a Sea Grant institute. Be prepared to describe when and where you caught the fish (the name of the lake or stream, and the nearest town). New sightings can be confirmed only by identification of a captured fish. Verbal reports cannot be used because sculpins can be easily mistaken for gobies.
Species and Origin: Rusty crayfish are crustaceans that grow up to 5 inches long. They are native to the Ohio River basin. Their carapace usually has a pair of rusty-colored spots and claws often have black bands at their tips.
(Orconectes rusticus)
What does a rusty crayfish look like?
Rusty crayfish can be identified by their robust claws, and by dark, rusty spots on each side of their carapace. The spots are located on the carapace as though you picked up the crayfish with paint on your forefinger and thumb. The spots may not always be present or well developed on rusty crayfish from some waters.
Competition with Native Species - Being an aggressive species, the rusty crayfish often displaces native or existing crayfish species.
Destruction of aquatic plant beds - When introduced, rusty crayfish reduce aquatic plant abundance and species diversity. This can be especially damaging in relatively unproductive northern lakes, where beds of aquatic plants are not abundant. Submerged aquatic plants are important in these systems for habitat for invertebrates (which provide food for fish and ducks), shelter for young gamefish, or forage species of fish, nesting areas for fish, and erosion control.
Anglers - When rusty crayfish are introduced to a new system, the impacts are potentially devastating. However, because of the nature of these impacts, it takes time for anglers to directly feel these results.
SCUBA Divers - Part of the lure of SCUBA diving is seeing life underwater. With the introduction of rusty crayfish, the benefit of seeing the diversity of underwater life will decrease.
Swimmers - In the heavily-infested northern Wisconsin and Minnesota lakes, recreational swimming has been affected because large numbers of rusty crayfish now occupy favorite swimming holes.
Rusty crayfish are thought to be native to the Ohio River Basin, particularly throughout the states of Ohio, Kentucky, Tennessee, Indiana, and Illinois. Now this species is found in a number of northern states, and provinces in Canada.
How can I prevent the spread of rusty crayfish? Specifics to prevent the spread of species.
Become knowledgeable about the crayfish native to your area,
Be able to identify the rusty crayfish
Do not release live bait into any waters
There are several laws that limit boating and transport of the species in some places.
(Petromyzon marinus)
Identification: Becker (1983); Page and Burr (1991); Jenkins and Burkhead (1994); Vladykov and Kott (1980) provided a key to the ammocoetes of lampreys found in the Great Lakes region. Eel-like in appearance, but not an eel. Sea lamprey is a cartilaginous fish without jaws. This species has two close dorsal fins, no paired fins, seven gill openings, and a large round mouth with sharp, curved teeth. (Page and Burr 1991; Jenkins and Burkhead 1994).
Size: 120 cm anadromous; 64 cm landlocked
Native Range: Generally marine but ascends freshwater rivers to spawn.
Nonindigenous Occurrences: Lamprey was first discovered in Lake Ontario in 1835, Lake Erie in 1921, Lake Michigan in 1936, Lake Huron in 1937, and Lake Superior in 1946 (Applegate 1950; Lawrie 1970; Smith 1979; Smith and Tibbles 1980; Smith 1985). Its distribution in all five Great Lakes and selected tributaries includes several different northern states.

This species was formerly believed to be introduced into the Finger Lakes and Lake Champlain in New York and Vermont (Lee et al. 1980 et seq.). However recent genetic evidence shows it is native to these areas (Bryan et al. 2005).

Means of Introduction: Controversy exists as to whether the sea lamprey is native to Lake Ontario. Several believe it is native (e.g., Lawrie 1970; Smith 1985), suggesting that sea lamprey found in Lake Ontario and its tributaries, the Finger Lakes, and Lake Champlain represent relict populations from the last Pleistocene glaciation. Those contending that it is not native believe that this species, unknown in Lake Ontario prior to the 1830s, had most likely entered the inland lake from Atlantic coastal drainages via the artificially created Erie Canal (e.g., Emery 1985). Whether or not the sea lamprey is native to Lake Ontario, this species is not native to the other Great Lakes and tributaries where it is now readily found.
Impact of Introduction: Attack and parasitic feeding on other fishes by adult lampreys often results in death of the prey, either directly from the loss of fluids and tissues or indirectly from secondary infection of the wound (Phillips et al. 1982). The species' introduction to the Great Lakes and its later abundance, combined with water pollution and overfishing, resulted in the decline of several large native species, including several ciscoes Coregonus spp., lake trout Salvelinus namaycush, and walleye Sander vitreus, among others.
(Bythotrephes longimanus)
Species and Origin: Spiny waterfleas are zooplankton (microscopic animals). Native to Europe and Asia, they were introduced into the Great Lakes by ballast water discharged from ocean-going ships. They were first discovered in Lake Ontario in 1982 and spread to Lake Superior in 1987. Adults range from 1/4 to 5/8 inch long. Spiny waterflea have a single long tail with small spines along its length.

Impacts: Spiny waterfleas eat small animals (zooplankton), including Daphnia, which are an important food for native fishes. In some lakes, they caused the decline or elimination of some species of native zooplankton. They can clog eyelets of fishing rods and prevent fish from being landed.

Status: They have spread throughout the Great Lakes, and are established in some inland lakes and rivers in Minnesota. See US map This link leads to an external site..

Means of spread: They can spread by attaching to fishing lines, downriggers, anchor ropes, and fishing nets. While female waterfleas die out of water, under certain conditions they produce eggs that resist drying and freezing, and can establish a new infestation. They also can be unintentionally transported in bilge water, bait buckets, or livewells.

Where to look: They collect in gelatinous globs on fishing lines and downrigger cables. They prefer deep lakes, but can be found in shallow lakes and rivers.

Regulatory Classification: Spiny waterfleas are a regulated invasive species in Minnesota (DNR), which means introduction into another waterbody is prohibited.
Control: Be vigilant about cleaning all of your equipment. Clean all downgrigger
cables and monofilament lines on reels (plucking like a guitar string helps) to prevent
carrying spiny waterfleas to another lake or river. Learn to recognize waterfleas on
fishing gear, they will be a gelatinous or cotton-ball like material on lines near
connections with lures, swivels, or downrigger balls. Drain lake or river water from
livewell and bilge before leaving the access. Dispose of unwanted live bait in the trash.
Law: Iowa law makes it illegal to 1) possess, introduce, purchase, sell, propagate, or
transport aquatic invasive species in Iowa, 2) place a trailer or launch a watercraft with
aquatic invasive species attached in public waters, and 3) operate a watercraft in a
marked aquatic invasive species infestation. The scheduled fine is $500 for violating
any of the above regulations. The law also requires the DNR to identify waterbodies
infested with aquatic invasive species and post signs alerting boaters. The DNR may
restrict boating, fishing, swimming, and trapping in infested waters.
(Rapana venosa)
Native To: Western Pacific Ocean (Mann et al. 2004)

Date of U.S. Introduction: First discovered in 1998 (Mann et al. 2004)

Means of Introduction: Probably in ballast water (Mann et al. 2004)

Impact: Preys on bivalves, such as clams, oysters, and mussels (Mann et al. 2004)

IDENTIFICATION: The shell is globose (rounded), with a very short-spire and large body whorl. The epidermal color varies from gray to reddish-brown, with dark brown dashes on the spiral ribs. Most specimens have distinctive black veins throughout the shell. A diagnostic feature for this species is the deep orange color found in the aperture and on the columella. Rapa whelks can reach 180 mm (about 7 in).

NATIVE RANGE: Marine and estuarine waters of the western Pacific, from the Sea of Japan, Yellow Sea, East China Sea and the Bohai Sea.

Rapa whelk (Rapana venosa) - click to enlarge
Veined Rapa Whelk, Rapana venosa (Actual size of specimen is ~6 in/152 mm) (Specimen courtesy of Julia Harding, VIMS)
LIFE HISTORY: Veined rapa whelks are carnivorous gastropods whose main diet consists of a variety of other mollusk such as native oysters. Most marine predatory snails feed by drilling a hole into their prey, but rapa whelks smother their prey by wrapping around the hinged region of the shell and feeding between the opened valve. It reproduces by laying clusters of egg capsules that resemble small mats of yellow shag carpet, which produce pelagic larvae that eventually settle on the bottom where they develop into hard-shelled snails. Growth is rapid over the first year of life, reproduction occurs from the second year onwards and large specimens may be over ten years old.

HABITAT: This species favors compact sandy bottoms where it can burrow deep into the substrate. The native habitat is a region of wide annual temperature ranges, comparable to the Chesapeake Bay. It may migrate to warmer, deeper waters in winter thereby evading cool surface waters. This prolific species is extremely versatile, tolerating low salinities, water pollution and oxygen deficient waters.

NONINDIGENOUS OCCURRENCES: Rapana venosa has been introduced into the Black Sea in the 1940s and within a decade spread along the Caucasian and Crimean coasts and to the Sea of Azov. Its range extended into the northwest Black Sea to the coastlines of Romania, Bulgaria and Turkey from 1959 to 1972. This species has been introduced and become established in the northern Adriatic and Aegean seas and is present at a location along the southeast coast of South America. The first specimen in the United States was collected by members of the Virginia Institute of Marine Science Trawl Survey Group in August 1998 in Hampton Roads, VA. Adult specimens as well as egg cases continue to be reported from locations in lower Chesapeake Bay.

MEANS OF INTRODUCTION: Possible pathways of introduction in the Chesapeake Bay area include planktonic larvae in ballast water tanks of ships or egg masses that may have been transported with products of marine farming.

IMPACTS: Veined rapa whelks have caused significant changes in the ecology of bottom-dwelling organisms, and have become marine pests in the Black Sea. Although scientists are still studying the impacts of the whelk, they are very concerned about its potential damage to native Bay species. Studies are currently under way to help determine the whelk's spread in the Chesapeake Bay, so that scientists can develop a model that will help define potential impacts to the Bay's ecosystem.

US map - click to enlarge
Red area denotes general vicinity of established population in the US. (Lower Chesapeake Bay)
CONTROL AND MANAGEMENT: There are no known cases of successful eradication of nonindigenous marine invertebrates in the United States. Studies are under way at the Virginia Institute of Marine Science (VIMS) to help determine the whelk's spread and its potential environmental range. VIMS researchers are interested in any sightings of this species in Virginia and Maryland waters. The institute is also paying watermen a bounty for live and dead whelks, to determine the rate and directions of spread. Current studies are investigating the extraordinary reproductive habits of the whelks. In Hampton Roads, watermen and researchers have discovered the whelks laying millions of egg cases. Potential for damage to native shellfish populations is considerable. The more scientists are learning about this species the more concerned they become about the region's seafood industry.
Reproduction and Life Cycle:
During warmer months, rapa whelks lay groups of egg cases attached to rocks and other hard surfaces. Rapa whelk egg cases look like small mats of yellow shag carpet. Each egg case is approximately 2 inches tall and one-quarter of an inch thick. In approximately 18 to 26 days, tiny, free-swimming larvae hatch from a small hole at the top of each egg case. After 4 to 6 weeks, larvae settle to the bottom and eventually grow into hard-shelled adults. Young grow rapidly during their first year and can reproduce by their second year. Rapa whelks can live longer than 10 years.
(Phyllorhiza punctata)
Native To: Australia and the Philippines (Graham et al. 2003)
Date of U.S. Introduction: First discovered in 1981 in California (Carlton and Geller 1993)
Means of Introduction: Probably entered from the Pacific Ocean through the Panama Canal on the hulls of ships (Graham et al. 2003)
Impacts: Preys on native species; negatively impacts shrimp industry by clogging nets and damaging fishing equipment (Ocaña-Luna et al. 2010)
Current U.S. Distribution: Southeastern U.S. coastal region
The bell of this large jellyfish may reach 50 cm in diameter. It is typically bluish-brown with many evenly distributed opaque white spots. It has eight thick transparent branching oral arms which terminate with large brown bundles of stinging cells. From each oral arm hangs a longer ribbon-like transparent appendage.
A superficially similar, but smaller species of jellyfish, Mastigias sp., is also thought to be an alien.
In Hawaii these jellyfish are found swimming near the surface in the murky waters near estuaries in harbors and embayments. Nothing is known about the habitat of the tiny benthic stages of this species in Hawaii.
Hawaiian Islands
Oahu - Pearl and Honolulu Harbors, Ala Wai Canal and Yacht Harbor, Kaneohe Bay.
Native Range
Present Distribution
Australia, Hawaiian Islands, Caribbean, Gulf of Mexico.
Mechanism of Introduction
Unintentional, as ship-fouling scyphistomae or as ephyrae in ballast water.
Ecological impact unstudied in Hawaiian Islands, but these jellyfish are known to eat planktonic crustaceans and fish eggs and larvae elsewhere. A population explosion of P. punctata in the Gulf of Mexico, where it is an alien species, appeared to threaten the local fish populations and other commercially important species such as shrimp, menhaden, anchovies, and crabs. No comparable population fluctuations are known to occur in Hawaiian waters, but it has been reported that this jellyfish appears to be more common in winter months.
Phyllorhiza has stinging cells or nematocysts in its tentacles, which are used for protection and capturing plankton.
Basic cnidarian reproduction involves an asexually reproducing polyp stage, alternating with a sexually reproducing medusoid stage. This reproductive strategy is known as "alternation of generations". The scyphozoan reproductive cycle is typically dominated by the medusoid stage. The adult planktonic medusa is commonly referred to as a jellyfish. The planktonic planula larvae of the sexually reproducing medusa typically settles to the bottom where it attaches and grows (scyphistoma stage). It may then either directly form additional scyphistoma via a process of budding, and/or develop into a strobila, a benthic form which asexually produces and releases young medusa known as ephyrae. This alternation of generations may facilitate the transport of jellyfish by shipping through ballast water (planktonic planula, ephyrae or medusa) or fouling (benthic scyphistoma or strobila).