Introducing nonnative species can cause significant harm to native ecosystems. As they did not evolve along with their native counterparts, they posed numerous challenges to control and eradicate. Here are some ways the aquarium trade may contribute to the introduction of nonnative species. Listed below are some of the ways aquarium trade may harm native ecosystems:
Impacts of introducing nonnative species
Nonnative species are introduced into the marine environment by several means, including human-mediated vectors, habitat alteration, and fishing activities. Some of these introducers may disperse along coastlines by floating as larvae or attaching to floating materials. Others may enter the U.S. through human-mediated vectors such as the aquarium trade. Most recent efforts have focused on understanding new species’ mechanisms to enter U.S. waters. However, only a limited number of studies quantify how nonnative species spread along coastlines, which are essential for predicting the rate of introductions.
The rate of introductions in U.S. waters has increased exponentially since the 18th century and shows no sign of slowing down. Between 1961 and 1995, one new species was introduced to the San Francisco Bay. Other introductions are more likely to occur in places with poor environmental conditions, including invertebrates. However, nonnative species can cause significant harm, and it is necessary to avoid their introduction.
Introduced species can also alter ecosystem structure, biodiversity, and interactions among native species. They can alter nutrient cycling, energy flow, and species interactions. They may even become dominant in an ecosystem, making it more difficult for native species to survive and reproduce. This is not only detrimental to native species but can also reduce their competitiveness with introduced species. However, some aquarium owners deliberately introduce nonnative species to their tanks, resulting in an increased risk of release.
Regulations of the aquarium trade are likely to be the most effective method of combating the introduction of nonnative species. If these efforts are successful, introducing these nonnative species to the wild will cease to be an issue. However, they must be accompanied by education and public awareness campaigns. With increased public awareness, these efforts are likely to be a success. So, it will take some time before new species are introduced into the wild.
Invasive species pose threats to humans, the environment, and the economy. They predate, hybridize, and compete with native species. They also disrupt habitats and alter trophic webs. Currently, 54 percent of aquatic native species have been eradicated due to the introduction of exotic species. In North America, 70 percent of all extinctions are attributed to nonnative species. And the aquarium trade is growing fast – up to $160 million in the last decade, paralleling the rise in exotic species.
Introducing nonnative species into the aquarium trade is a significant contributor to the spread of invasive species. Many nonnative species did not evolve with the native species. This makes it difficult to control their spread. Biocontrol strategies rely on predators and pathogens to combat these species. Biocontrol efforts also require lengthy tests to ensure that these chemicals have minimal effect on non-target species.
Impacts of introducing nonnative species on native ecosystems
The introduction of nonnative species into ecosystems causes both positive and negative effects on the native biota. Nonnative species can be beneficial to native ecosystems and can even be beneficial in land reclamation. The impact of these introduced species is dependent on their mechanisms of action. For example, invasive species can alter plant populations through grazing or indirect effects by affecting the habitat of native plants and animals.
Introduced species may disrupt the ecological balance of the environment in different ways. Invasive species may cause habitat loss and extinction of native species by competing for space. Other introduced species may also carry pathogens and parasites and disrupt native ecosystems by causing habitat destruction. Several species may become established in an ecosystem but remain a long-term problem. Many successful projects have been undertaken to control the impact of nonnative species.
Several studies have documented the adverse effects of invasive nonnative marine and estuarine species. For example, in Puget Sound, the highly invasive S. alterniflora has turned bare mudflats into monocultures. The nonnative plant was accidentally introduced into the region in the 1890s as packing material for oysters. It is now infesting nearly 36 solid hectares in Port Susan Bay and Willapa Bay.
In some cases, introduced species may benefit native species. For example, a Japanese white-eye bird may spread the seeds of a native vine. Nevertheless, the relationship between introduced and native species is not well-defined. A new paper published in Conservation Biology suggests that the two species are unrelated. It is unclear if the paper’s authors recommend that the two species be kept separate.
The introduction of nonnative species to the U.K. is a growing ecological concern. However, in the U.K., there has been very little research on its impact on ecosystems. Despite the potential negative impacts, the U.K. has been lucky in introducing nonnative species to its landscape. A recent study by Hodder & Bullock (2001) showed that a small number of introduced species might have detrimental effects. Although the effects of nonnative species are not yet fully understood, the general decline in U.K. biodiversity and future climate change may make ecosystems more susceptible to invasions.
Despite the many negative impacts of introduced species, there are some positive ones. The monarch butterfly, for example, eats milkweed and has a neutral impact on native plants. In a cattle-dominated area, dung beetles are helping to control fly populations. In urban areas, the use of nonnative earthworms significantly improved soil quality. But this is not the whole story.
There is a complex relationship between introduced species and native species. A study in Chile showed that a gelatinous invertebrate could create massive mats off the coast. These mats provide a habitat for other organisms. Several other studies have shown that invasive species can enhance biodiversity. They may act as ecosystem engineers, but the long-term effects of introducing new species are not as clear.
Ways in which the aquarium trade contributes to the introduction of nonnative species
The aquarium trade introduces many exotic species to ecosystems worldwide, and many of those species may eventually escape and become invasive. Whether or not these animals are successful depends on factors such as climate, trophic guild, and fecundity. Although the aquarium trade may be the least harmful of these factors, it is still one of the most important contributors to introducing new species into ecosystems.
The introduction of nonnative species can have serious adverse effects on local ecosystems. Because they lack a natural check, nonnative species are often aggressive and outcompete native species. These species may disrupt the natural balance of ecosystems and deplete biodiversity in the area. These species can also introduce disease and pests, which can harm the native species. Further, the aquarium trade may be contributing to the introduction of invasive species.
Marine debris is an ongoing problem across the globe. After the tsunami, debris continues to spread by wind and ocean currents. For example, a ghost ship was found off the coast of Southeast Alaska, and a dock was found on the beach in Oregon. This marine debris may contain invasive nonnative species that may survive the journey across the Pacific Ocean on these items. The Aquatic Nuisance Species Task Force has established a protocol to respond to such situations if marine debris contains living organisms.
Introducing nonnative species can be caused by intentional releases or accidental escapes from the aquarium. Accidentally released lab animals can be a source of introductions, and the aquarium trade is no different. Intentionally released aquatic pets and aquarium plants can be spread by people who care for them, and releasing them into the wild can lead to the release of invasive species.
The aquarium trade has also contributed to introducing nonnative species into the Guianese freshwaters. This is most likely a result of two different human activities. First, fish hobbyists likely release ornamental species into the river, and second, aquariums dump them. The latter is likely the case for Pterophyllum scalare.
Another meaningful way the aquarium trade contributes to the spread of nonnative species is by introducing exotic animals into natural habitats. For example, brown tree snakes were accidentally introduced to Guam and are responsible for the extinction of nine native species of birds and other animals. However, this is far from the only impact of aquariums on the Everglades.