Filed Under (SW11) by Michael Di Nunzio on 10-11-2010

Michael Di Nunzio


In “Marine invasive species: validation of citizen science and implications for national monitoring networks”, Delaney et al. attempt to assess the capacity for citizen science to produce accurate data. The authors first express the pressing concerns posed by invasive marine species and their rapid proliferation. Monitoring the movements of these organisms is key to ecological preservation efforts, yet maintaining a sufficiently robust database of species location and prevalence is extremely costly and time-consuming. To reduce the excessive need for funding and personnel, Delaney et al. propose that citizen science data meeting quality control criteria be used to expand the knowledge database. Ideally this will increase both public knowledge and the amount of information available to researchers.

In their study, Delaney et al. opted to focus on Carcinus maenas and Hemigrapsus sanguineus, invasive crabs known for their ability to spread quickly. Several quadrats were randomly established during low tide and the crabs being considered were carefully collected. After this 190 groups of individuals varying in age and education level were asked to determine the species, gender, and carapace width of crabs in their particular sample. Statistical analysis was subsequently applied to the results and correlations between the characteristics of an individual and his or her accuracy were drawn. A positive correlation was found between education and ability to distinguish crab species, and the same was observed for age. Determination of crab gender proved more difficult across all groups, but no effect was observed as a result of group size or crab size on ability to distinguish species or gender. Data from individuals meeting requirements corresponding to 95% accuracy were then used to depict the distributions and relative densities of the invaders over the sampling range.

Delaney et al. endorse the use of citizen science, yet stress the need for a universal means of compiling data if this technique is to be viable. They suggest that this be accomplished through the use of some kind of easily accessible computer database, preferably linked with some kind of mapping program. On a final note the authors state a need for additional research that uses different sampling methods and sampling intensity to determine optimal resource allocation and probability of false-negatives.

Filed Under (SW10) by Shane Stone on 28-10-2010

Biol Invasions Vol 11:2223–2232, 2009.

The golden apple snail (Pomacea canaliculata), is native to South America, but has invaded many Asian countries. As its numbers have increased, the golden apple snail has heavily grazed upon plant life. Limited methods have been found to control the snail population, but biocontrol may be a viable option. Some researchers have suggested that the Common carp (Cyprinus carpio) could efficiently control the population, but the side effects of its usage are unknown.

Pak Ki Wong, King Lun Kwong, and Jian-Wen Qiu, of the Department of Biology at Hong Kong Baptist University, decided to engage in an 8-week study to determine whether the common carp could be used. They studied the carps’ effect on 3 aquatic macrophytes and 9 snails (including the golden apple snail). Results indicated the carp removed juvenile golden apple snails, but did not significantly affect the adult population. They concluded that it could be used to reduce the golden apple snail population, but hat caution be taken because if can affect other species too.

Filed Under (SW7) by Shane Stone on 11-10-2010

BMH Larson’s “The war of the roses: demilitarizing invasive biology” is a paper addressing how invasive species are portrayed to society. Those who research the species understand the effects that the species have on an ecosystem. However, to explain these scientific aspects to the general public would be inefficient because it would not capture their attention and interest. Therefore, Larson explains that militaristic metaphors are used to get the reader’s attention. He continues that these methods, although effective, are not in the long-term going to be useful. An example of this is seen on the National Geographic series “Strange Days on the Planet Earth- Invaders.” The Narrator, Edward Norton, says the invasive species are an “Alien species…think of them as the first wave of an assault that could drive the greatest extinction since the end of the dinosaurs” (Norton 2005).  This metaphor is extremely effective, and gets the point across. Larson acknowledge this, but as mentioned he understands that this is a hyperbole and in the long run may be an inadequate description. Larson’s paper actually reminds of an anti-war paper. If most papers are thought as pro-war propaganda then Larson’s work is like a pacifist trying to provide an alternative point of view.

Although I understand Larson’s point of view on the metaphors and understand the negative effects they may potentially have, I believe that their use must be continued. Larson explains alternative metaphors that can potentially be used, but none have the same impact. The idea of describing the invasive species as a disease would probably be just as effective, but as Larson suggests it would still become militaristic. For example, the “Fight against Cancer” is still militaristic. It is unfortunate, but in today’s media the best way to make people care about something, there needs to be conflict where a side can be taken. By providing a side, viewers and readers and create an emotional tie with a side and leads to involvement. Until a more efficient metaphor or strategy can be found to get the public involved can be found, I support the continued use of the militaristic metaphors.

National Geographic’s Strange Days on Planet Earth. Dir. Mark Shelley (Ii). Perf. Edward Norton. National Geographic Video, 2005. DVD.

Larson, BMH 2005. The war of the roses: demilitarizing invasive biology, Frontiers in Ecology  and the environment 3: 495-500.

Filed Under (SW5) by Shane Stone on 23-09-2010

Mar Ecol Prog Ser. Vol. 401: 291–294, 2010.

Since its introduction into Florida nearly a decade ago, Pterois volitans, the Lionfish, began its invasion of the coral reefs in the West Atlantic, especially in the Bahamas. In its non-native habitat, the Lionfish has become much more productive and successful than in its native home, because there are limited predators once it reaches adulthood. With the increase in Lionfish, there is a decrease in native fish recruitment.

Andrew B. Barbour,of the University of Florida, and his colleagues decided to answer the question of this invasive phenomenon. Do the Lionfish have an affect on the decreased recruitment? They  hypothesized that the Lionfish have been living in the mangroves that the native species use to reproduce. To test this, researchers checked the mangroves and examined stomach contents of the lionfish. In the contents, the scientists found remnants of species that are found within the Mangrove. With this analysis, the scientists concluded that the Lionfish had been preying on fish in the mangroves, most of which are juvenile. This has lead to increased juvenile mortality and therefore, the researchers believe, has lead to decreased recruitment. Despite their finding, the researchers hope for more in depth studies to be held.

Filed Under (SW2) by Shane Stone on 08-09-2010

“Strange Days on Planet Earth” is a documentary created by National Geographic and narrated by Edward Norton. It was created to provide a general audience with a glimpse at a problem that is plaguing the global community. The documentary details the problems associated with invasive species and provides examples from Uganda to New Orleans. Each example shows a different facet of the problem that the global community faces. The documentary opens with Jim Carlton’s work in an Oakland Port. He is in the process of making one of twenty rapid assessments in the area to determine new species in the area. His introduction is brief, but he is reintroduced later.

The viewer sees Claudia Riegel’s research of the Formosan subterranean termite. An invasive species introduced to America after the September 1945 Japanese surrender. When the Americans left they made crates from local wood, but the termites were in the wood. Once in America, the termites prospered in New Orleans because its climate is hot and sticky, similarly to the termites’ native land, and Orleans is composed mostly of wood. The termites then out competed native species because they can live above and below ground unlike the natives, which are only, settle below ground. The viewer even sees the efforts being made to eliminate the species.

Next, James Ogwang’s efforts to save Uganda’s Lake Victoria are shown. Here the viewer sees how the water hyacinth brought Uganda to its knees. Although the events in this part are quite riveting, details will be saved for SW3.

Finally, the documentary shows David Duffy’s research in Hawaii. In Hawaii, Duffy and Greg Asner are working to stop the miconia from destroying the island. The plant was brought to the island as a gift from Europe, but it soon got into the wild and began to outgrow surrounding vegetation. The growth began to shade lower growth until only miconia remained in the area. Areas where this occurred now have loose soil and are therefore prone to landslides. Asner is trying to find miconia colonies by determining how they reflect the sun and using this to find them from the air.

“Strange Days” then shows the viewers that scientists are not the only people contributing to these efforts. Civilians all over the world volunteer to help. In Uganda local fisher are helping to fight the water hyacinth. In America, the Weed Warriors are helping to eliminate the ice plant in their state.

The documentary is put together quite well and provides excellent insight for those who do not know very much about this issue. National Geographic’s usage of the word invaders became a motif present throughout the documentary. Edward Norton primarily uses when he describes the invasive species like they are an invasive alien army. He uses words and phrases such as “alien powers”, “invader assault”, and “encounter with aliens.” These puns provide brief levity to a serious matter. Also, I found one statistic to be quite powerful; 99% of the species in San Francisco, by weight, are foreign. An impressive and powerful statistic that ends an informative documentary.

Filed Under (SW1) by Bryan Lockwood on 02-09-2010
(USGS Photo)

Asian Swamp Eel (USGS Photo)

First discovered in Georgia in the year 1994, the slippery Asian swamp eel has slivered its way to becoming one of the most versatile invasive aquatic species in America. This poses a major threat to ecosystems all across the nation. For example, Fish And Aquatic News states that not only has the Asian swamp eel been found in the warm, humid climates of Florida and Georgia, but also in New Jersey where a drastic contrast of freezing temperatures is blatantly evident. Lakes and wetlands of all climate regions are susceptible to invasion by the eel, and its survival capabilities make it extremely difficult to get rid of. If there is a scarcity of water in the eel’s habitat, it can survive by burrowing underground into moist soil,  not to mention its ability to survive on land for long periods of time by absorbing oxygen through its skin. This species is a terror to the wildlife in America, even more so to the sensitive endangered species such as those in Florida’s Everglades.

This problem hit very close to home for me because Florida just happens to be my birthplace. The very large city surrounding the equally massive St. John’s River became my beloved habitat, and an invasion of any kind would not be taken lightly. Scientists say that they may not be able to stop the growth of these eels, but electroshocking and poison are two ways that the invasion can be slowed down. The Asian swamp eel is trying to claim territory in multiple locations in the U.S. and although National Parks Traveler says that it has yet to cause significant ecological damage, I do not think that we should sit around clicking our heels until it does.