Alien Invasion 250 Pink Dna

[Charlotta Menchaca]

Our15oz ceramic coffee mug with an alien head is perfect for any sci-fi fan! Available in black, green, or pink, this mug features the words Roswell, NM below the head, making it the perfect souvenir or gift for anyone who loves extraterrestrial themes. With its sturdy ceramic construction, this mug is great for enjoying your morning coffee, tea, or any other hot beverage. Grab one today and add a touch of intergalactic fun to your drinkware collection!

Sign up for our monthly newsletter to keep up to date with things going on in the shop and around Roswell! Those who sign up will be entered into our weekly t-shirt giveaway! We'll draw a winner every single week! If you're chosen, we'll email you to get your size and shipping info. No purchase necessary to win!

This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.

In 2017, Norway experienced an invasion of the Pacific salmonid pink salmon (Oncorhynchus gorbuscha) in numbers never before seen in rivers all along the coast. Significant numbers were also caught in other parts of northwestern Europe. Pink salmon has been observed in variable numbers in Norwegian waters in the summer and autumn of most years since 1960, after the first successful Russian introduction of pink salmon fry in rivers draining to the White Sea in northwest Russia in 1959. With the exception of 1960, pink salmon have been most abundant in odd years, based on the odd-year broodline of the 2-year life salmonid. Even-year fish has generally been less abundant, but in recent years, significant numbers of this broodline have also been caught. In this paper we review the available information on pink salmon in Norwegian rivers and discuss (1) to what extent the presence of this species in Norway has been driven by Russian introductions and natural reproduction in Russian, and lately in Norwegian, rivers, and (2) the likelihood of reproducing populations of pink salmon being established in more Norwegian rivers. Considering the continued propagule pressure in terms of adult pink salmon entering and spawning in Norwegian rivers, it is puzzling that self-propagating populations apparently only have been established in some rivers in the northernmost part of the country. The potential impact of pink salmon on native salmonids and river ecosystems is discussed briefly. Extensive research is required to understand the mechanisms that determine the fate of pink salmon as an alien species, and specifically the possible impact of pink salmon on native salmonids and the environment in the recipient rivers and in the ocean.

The introduction of non-native species is considered one of the major threats to native biodiversity and ecosystem services (Rahel 2002; Pejchar and Mooney 2009). Introductions happen when species are moved outside of their natural range by humans (Falk-Petersen et al. 2006). This may happen accidentally, or with the goal of establishing new populations. Purposeful introductions are commonly motivated by economy, subsistence or recreation, and have occurred throughout human history. Most groups of organisms have been involved, including mammals, fishes, birds, reptiles, amphibians, invertebrates and plants (Olden et al. 2011). There are some well-documented examples among salmonid fishes which have been spread over most of the world, such as brown trout (Salmo trutta) (MacCrimmon and Marshall 1968), and several Oncorhynchus species (Crawford and Muir 2008).

The impact of species introductions is associated with the ability of the established alien species to spread and establish in more localities than the original target locality. Secondary spreading is perhaps the greatest challenge for management, because it becomes impossible to contain unwanted species with a large ability to disperse.

Species of the salmonid genus Oncorhynchus have for decades been introduced to innumerable localities outside their native range (Crawford and Muir 2008). For instance, rainbow trout (O. mykiss), which is native to western North America, was first introduced in Europe in the late 1800s, and is now one of the most widely introduced fishes on a global scale, present on all continents except Antarctica (MacCrimmon 1971; Stankovic et al. 2015). Another example of a large-scale and long-term introduction of Pacific salmon is the release of millions of fertilized eggs or fry of pink salmon (O. gorbuscha) from rivers on the Russian Pacific to rivers in Northwest Russia, draining to the White Sea (Bakshtansky 1980).

Pink salmon has a wide native range in the northern Pacific. On the North American side, it previously occured in rivers from the Sacramento River, California (38N latitude) to and around the northern tip of Alaska (71N). In rivers on the Eurasian continent, it has been recorded from Korea (37N) to the river Lena in Siberia (73N) (Heard 1991). However, the most abundant populations are found in the northern part of this area (from Alaska to Puget Sound (48N) and from Siberia to southern Sakhalin (40N); Ruggerone and Irvine 2018). It appears that the abundance and the number of populations decrease in the south, while the northern distribution is expanding (Radchenko et al. 2018).

The history and results of the introduction of pink salmon in Russian waters have been relatively well documented, in Russian as well as in English (Dushkina 1994; Chereshnev et al. 2002; Zubchenko et al. 2010). The early secondary spreading and possible establishment of this species in Norwegian waters were also documented (Berg 1961, 1977; Bjerknes and Vaag 1980). Since the first observations in Norway in 1960, pink salmon has been an irregular element in Norwegian fauna. In some rivers in the northernmost part of the country (around 70N), pink salmon have been observed in most years, although in widely varying numbers (Berg 1977; Niemel et al. 2016). Further south, numbers have in most years been low. However, in 2017, pink salmon were observed in rivers along the entire coastline, and in high numbers in many rivers (Mo et al. 2018). In 2017, pink salmon was also caught in rivers in the UK and Ireland, in countries in mainland western Europe, as well as in Iceland and on the east coast of Canada (Bartlett 2017; BBC 2017; Whelan 2017; Armstrong et al. 2018).

Here we provide a review of the ecological characteristics of pink salmon and its secondary spreading to Norwegian waters after the transplantation to rivers in north-western Russia. We describe the complicated history of pink salmon in Norway and discuss the various factors that may have influenced the observed development, and the potential for future establishment. The aim is to understand the dynamics of this unusual case of secondary spreading of a potentially invasive species. Interactions between pink salmon and Atlantic salmonids in rivers are little known, but the extent of potential impacts is substantial, considering that, along the Norwegian coast from the border to Russia in the northeast to the border to Sweden in the southeast, there are approx. 450 rivers with anadromous Atlantic salmon (Salmo salar), more than 1000 rivers with anadromous brown trout, and, in the three northernmost counties, more than 100 rivers with anadromous Arctic charr (Salvelinus alpinus). The extent of possible interactions in the marine environment is also unknown, but in the Pacific, abundant pink salmon are considered a serious competitor with other Oncorhynchus species (Ruggerone and Nielsen 2004).

Among the anadromous salmonids, pink (or humpback) salmon is one of the species with the most restricted residence time in freshwater. The adults enter the river a short time before spawning and they survive only a few weeks after spawning before they all die. All fry leave the river shortly after commencing external feeding (Heard 1991; Quinn 2005).

The 2-year life cycle of pink salmon has resulted in the evolution of so-called odd and even-year broodlines. Fish that spawn in odd years produce offspring that will spend one winter at sea and return to spawn in odd years, while the offspring of fish that spawn in even years spawn in even years. In most rivers in the native range, both broodlines occur (Gordeeva and Salmenkova 2011). Overall, within the native range in the Pacific, the relative abundance of the two broodlines has varied among regions (Irvine et al. 2014), although the odd-year broodline has generally been most abundant. Presently, the odd-year dominance seems to increase; the changes may be associated with climate change as well as large scale stocking with hatchery produced fish (Irvine and Fukuwaka 2011; Ruggerone and Irvine 2018).

The two broodlines are reproductively isolated from each other, but still the genetic differences between them is restricted (Olsen et al. 1998; Churikov and Gharrett 2002; Hawkins et al. 2002; Tarpey et al. 2018), not exceeding the general level of inter-population differences in salmonids (Althukov et al. 2000).

In spite of the substantial decline in catches of even-year fish since 2000, there is a variable but small catch of even-year fish in Russian rivers (between 30 kg and 11 tonnes). There is also a restricted, but quite regular, even-year pink salmon occurrence in Norwegian rivers. This indicates that in these non-native stocks, the even-year broodline is less productive in the wild than the odd-year broodline. According to Gordeeva et al. (2015) and Gordeeva (2017) the reason may be that, while the odd-year broodline was able to respond quickly to the severe natural selection pressure in the new environment, this was not the case with even-year fish.

Recorded occurrence of pink salmon in Norwegian rivers. Up to 2012: Rivers where pink salmon has been observed or caught before 2012 (Gjelland and Sandlund 2012). 2015, 2016 and 2017: Observations and catches during the last 3 years, including drift counting and video camera monitoring. Note that stocking in Russia stopped in 1999

3a8082e126