Volume 13, Issue 3 (2018)
published September 2018
Contents | |
Research articles |
|
-
|
Anita A.C. Pearson and Ian C. Duggan
A global review of zooplankton species in freshwater aquaculture ponds: what are the risks for invasion?
(pp 311–322)
|
|
Non-native freshwater zooplankton species have been recorded from aquaculture ponds in New Zealand and Italy, while zooplankton invasions
elsewhere have implicated the aquaculture industry as the vector for introduction. However, the prevalence of non-native species in international
aquaculture facilities is unclear. We undertook a literature review of publications examining zooplankton assemblages in freshwater aquaculture
ponds globally to determine; 1) the prevalence of non-native taxa, 2) the quality of the studies undertaken, 3) how well the major freshwater
aquaculture nations are represented in studies, and 4) the representation of dominant aquaculture species. Thirty-two suitable publications
were found that provided data on zooplankton assemblages from aquaculture facilities. We supplemented this by sampling Huka Prawn Park, Taupō,
New Zealand, as knowledge of zooplankton in prawn facilities was scarce. Zooplankton data was obtained for 205 outdoor ponds and experimental tanks,
from 39 different aquaculture facilities, across 13 countries. Non-indigenous taxa were recorded from 17.9% of facilities globally.
Over half of these publications (53.1%) identified taxa to genus level only, with the remaining 46.9% attempting species level identifications.
The high proportion of publications not identifying to species level indicates that non-native species will not be recognised in most studies;
31.8% of facilities were invaded when considering only studies with species level identifications. In total, 234 different taxa were identified
(including 184 to species level), with only 4, located in Italy and New Zealand, recognised as non-native; only 3 of these 4 taxa were clearly
identified as non-indigenous in their respective publications. Another species has been identified outside of its native range in North American
aquaculture facilities, but no co-existing zooplankton species were reported. While aquaculture facilities were found to harbour only a small
number of non-indigenous species, our findings indicate that there is a significant lack of taxonomic resolution used in most studies,
and a lack of surveys in major aquaculture producing regions and from facilities holding many of the major aquaculture species. Importantly,
few zooplankton invaders putatively originating from the aquaculture industry have been found within aquaculture facilities themselves.
Overall, it is currently difficult to determine the prevalence of non-indigenous zooplankton species in aquaculture facilities globally,
and our results suggest the risk may be far higher than is currently appreciated. As such, we recommend systematic surveys of ponds utilising
species level identification from a variety of geographic regions, to better quantify invasion risks by non-native zooplankton taxa from
the freshwater aquaculture industry. |
|
-
|
Michael J. Mangiante, Amy J. S. Davis, Stephanie Panlasigui, Matthew E. Neilson, Ian Pfingsten, Pam L. Fuller and John A. Darling
Trends in nonindigenous aquatic species richness in the United States reveal shifting spatial and temporal patterns of species introductions
(pp 323–338)
|
|
Understanding the spatial and temporal dynamics underlying the introduction and spread of nonindigenous aquatic species (NAS) can provide
important insights into the historical drivers of biological invasions and aid in forecasting future patterns of nonindigenous species
arrival and spread. Increasingly, public databases of species observation records are being used to quantify changes in NAS distributions
across space and time, and are becoming an important resource for researchers, managers, and policy-makers. Here we use publicly available
data to describe trends in NAS introduction and spread across the conterminous United States over more than two centuries of observation records.
Available data on first records of NAS reveal significant shifts in dominance of particular introduction patterns over time, both in terms
of recipient regions and likely sources. These spatiotemporal trends at the continental scale may be subject to biases associated with regional
variation in sampling effort, reporting, and data curation. We therefore also examined two additional metrics, the number of individual records
and the spatial coverage of those records, which are likely to be more closely associated with sampling effort. Our results suggest
that broad-scale patterns may mask considerable variation across regions, time periods, and even entities contributing to NAS sampling.
In some cases, observed temporal shifts in species discovery may be influenced by dramatic fluctuations in the number and spatial extent
of individual observations, reflecting the possibility that shifts in sampling effort may obscure underlying rates of NAS introduction. |
|
-
|
Lindsay M. Marks, Daniel C. Reed and Sally J. Holbrook
Life history traits of the invasive seaweed Sargassum horneri at Santa Catalina Island, California
(pp 339–350)
|
|
The recent spread of the Asian seaweed, Sargassum horneri (Turner) C. Agardh, along the Pacific coast of North America, presents
an opportunity to expand our understanding of traits of invasive macroalgae. Here we used surveys to characterize the life history
of S. horneri and to quantify traits that promote its spread and persistence, including seasonality in abundance and reproduction,
broad habitat affinity, and high reproductive capacity. We found that S. horneri occupies a wide range of suitable depths and substrates,
allocates substantial biomass to reproduction, and has seasonal patterns of biomass offset from that of most native macroalgae. A field experiment
revealed S. horneri has a high capacity for local dispersal and recruitment that appears sufficient for maintaining populations through
multiple generations. Our findings can be paired with knowledge of the life histories of co-occurring species to characterize their potential
to interact with S. horneri, which should prove useful for developing best practices for managing its spread. |
|
-
|
María Lourdes Jaubet, María Andrea Saracho Bottero, Emiliano Hines, Rodolfo Elías and Griselda Valeria Garaffo
Boccardia proboscidea (Polychaete: Spionidae) in the SW Atlantic: how far has the invasion spread?
(pp 351–363)
|
|
Boccardia proboscidea is an exotic polychaete that was introduced to a Southwestern Atlantic Ocean coastal area of Argentina
(Mar del Plata; Province of Buenos Aires). This polychaete proved to be a threat to local diversity as it displaced native species
and modified the natural intertidal community structure. However, nothing is known about its latitudinal distribution in the country
and the degree of its invasion. It is possible that due to deficiencies in taxonomy and lack of ecological studies, other localities
of the Argentine coast were also invaded by this polychaete but have not yet been registered. The goal of the present study was to survey
the latitudinal distribution of B. proboscidea in the coastal area of Argentina from 37ºS to 54ºS. In addition, this study aimed
to evaluate the type of substrate colonized, investigate the presence of sewage effluence as a conditional factor for B. proboscidea
establishment, and evaluate differences in the composition of species assemblages associated with the intertidal community invaded
by the polychaete. Boccardia proboscidea was found latitudinally from 37ºS to 47ºS. The highest abundance was found on hard substrates
and with intertidal sewage effluent. The opportunistic nature (r strategy) of B. proboscidea coupled with a continuous supply of organic
matter (sewage effluent) may indicate the mechanism that has led to the success of its introduction into new localities. |
|
-
|
Wen Ting Tan, Lynette H.L. Loke, Darren C.J. Yeo, Siong Kiat Tan and Peter A. Todd
Do Singapore’s seawalls host non-native marine molluscs?
(pp 365–378)
|
|
Marine urbanization and the construction of artificial coastal structures such as seawalls have been implicated in the spread of non-native
marine species for a variety of reasons, the most common being that seawalls provide unoccupied niches for alien colonisation. If urbanisation
is accompanied by a concomitant increase in shipping then this may also be a factor, i.e. increased propagule pressure of non-native species
due to translocation beyond their native range via the hulls of ships and/or in ballast water. Singapore is potentially highly vulnerable
to invasion by non-native marine species as its coastline comprises over 60% seawall and it is one of the world’s busiest ports.
The aim of this study is to investigate the native, non-native, and cryptogenic molluscs found on Singapore’s seawalls. Seven seawall
sites around Singapore were surveyed and all specimens found were either Indo-Pacific species or of unknown origin. To determine whether
there were potential non-natives from within the Indo-Pacific, a set of attributes concerning the history, biogeography, detectability,
human affinity, invasion pathway, biology, ecology, life-history, pre-history, evolution and genetics of mollusc species was collected from
available literature. Only one “possibly introduced” species, Siphonaria guamensis Quoy and Gaimard, 1833 (Gastropoda), was identified.
The remaining species consisted of 41 native to Singapore and 23 cryptogenic species. The results from this study add to the increasing pool
of literature showing that, contrary to widespread assumption, there is a very low occurrence of non-native marine species in Singapore. |
|
-
|
Rowshyra A. Castañeda, Emilija Cvetanovska, Kayla M. Hamelin, M. Anouk Simard and Anthony Ricciardi
Distribution, abundance and condition of an invasive bivalve (Corbicula fluminea) along an artificial thermal gradient in the St. Lawrence River
(pp 379–392)
|
|
The Asian clam Corbicula fluminea has been introduced to lakes and rivers worldwide, but its physiological requirements generally
restrict its distribution to water temperatures of ≥ 2 °C. In north temperate areas of North America, C. fluminea therefore occurs
primarily in artificially heated waterbodies. In November 2009, C. fluminea was discovered for the first time in the St. Lawrence River
within the thermal discharge plume of the Gentilly-2 nuclear power plant, in which the species had developed an abundant and persistent
population. In summer 2011, the distribution, abundance and body condition of C. fluminea were sampled in sections of the river
immediately upstream and for several kilometres downstream of the power plant. The thermal plume extended as far downstream as 4 km, and
C. fluminea’s population density declined along this distance. A generalized linear mixed model indicated that C. fluminea’s
local population density was related negatively to water depth and positively to temperature, turbidity and flow velocity, with temperature
having the greatest influence. At stations closer to the discharge source, clams were larger and had a higher mean body condition. However,
when temperatures exceeded 30 °C in the discharge canal during mid-summer, body condition was maximal outside the canal at 1.5 km downstream
of the discharge source. Thus, although the plume provided a winter thermal refuge for C. fluminea, it created a temperature gradient
that encompassed both the upper and lower tolerance limits of the species. The C. fluminea population was extirpated during the winter
months when normal temperatures were re-established following permanent cessation of power plant activity in December 2012. |
|
-
|
Michael A. McCartney and Sophie Mallez
The role of waterway connections and downstream drift of veliger larvae in the expanding invasion of inland lakes by zebra mussels in Minnesota, USA
(pp 393–408)
|
|
Zebra mussel spread to inland waters in Europe and North America is often attributed to overland transport by trailered boats
and water-related equipment. Much less attention is paid to spread between lakes connected by streams that may serve as conduits
for larval dispersal. Previous studies have produced few data on the magnitude and distance of downstream drift of veliger larvae.
Here we present an evaluation of the contribution of streamflow connections to zebra mussel spread, and new data on the numbers
of larvae transported from infested lake stream outlets. We studied lake/stream connections in Minnesota (MN) and found that
lakes connected to upstream infested lakes are 27 times more often infested than unconnected lakes. In 4 lake/stream systems and
at increasing distances downstream of infested source lakes, we estimated recruitment and larval “flux” (numbers per unit time),
and found recruitment to be localized, in most cases to within 1 km from source lakes. A short distance from lake outlets,
larval flux reached 109 larvae per day or more at peak times in the 2 systems with the highest supply. In all 4 systems,
flux dropped steeply and exponentially with distance. Nevertheless, flux reached 0 (observed) through the entire season,
and/or was below a low-risk threshold (estimated) at the downstream inlet (as far as 64 km downstream) in only 1 system.
Spread risk by downstream drift is so high that prevention and treatment efforts should be focused on upstream lakes
in pristine watersheds. At the same time, localized recruitment confirms that zebra mussel populations are unlikely
to persist far from source waters, limiting impact to unionids and other native species in small streams. |
|
-
|
Brett M. Johnson, William M. Pate, Douglas B. Silver and Julia L. Sharp
Invasion success and population characteristics of the opossum shrimp, Mysis diluviana, in Wyoming, USA
(pp 409–420)
|
|
Studying the colonization, distribution, demographics, and abundance of invasive species is important for understanding their invasion biology,
including the conditions required for establishment. This information can also be used to reduce their risk of spread. Opossum shrimp
Mysis diluviana Audzijonyte and Väinölä, 2005, is an invasive species in lakes and reservoirs of the western United States and Canada.
Four lakes in western Wyoming, USA, were stocked with this nonnative crustacean in 1971, but no Mysis surveys have been conducted
in Wyoming since 1981. We determined presence/absence, demographics, and abundance of Mysis in these and six nearby lakes that could
have been invaded using vertical net tows and environmental DNA analysis. Environmental conditions were compared in lakes with and without
Mysis, and we evaluated the potential for Mysis to disperse downstream. Mysis (> 500 individuals/m²) persisted in two
of the four stocked lakes and nowhere else. Both of the lakes with established populations had daytime light levels on the bottom below
the visual feeding threshold for fish, and the hypolimnia were oxygenated. Hierarchical cluster analysis of lake physicochemical conditions
grouped these two lakes with four others, all of which were deep (46–185 m), with high oxygen concentrations (> 3 mg/L) on the bottom,
and relatively low light intensities (< 0.2 lx) near the bottom. A second cluster of lakes that all lacked Mysis, and appeared
to be less suitable, were shallow (< 20 m), had severe hypolimnetic hypoxia, and higher light levels (≥ 590 lx) near the bottom.
The interaction of strong light penetration with lake depth, compounded by strong clinograde oxygen profiles, would prevent the formation
of a daytime predation refuge from fish in these lakes, reducing the likelihood of Mysis invasion. Given that only half
of the purposeful introductions in Wyoming were successful, and that there have been no new invasions in nearly 50 years, future range
expansion by the species in the region is unlikely without human facilitation. |
|
-
|
Hui Wei, Ratcha Chaichana, Fei Liu, Du Luo, Yu Qian, Dangen Gu, Xidong Mu, Meng Xu and Yinchang Hu
Nutrient enrichment alters life-history traits of non-native fish Pterygoplichthys spp. in sub-tropical rivers
(pp 421–432)
|
|
Nutrient enrichment caused by anthropogenic activities can positively affect biological invasions as novel species can utilize additional
resources in the ecosystem for population persistence. Although the effect of resource availability on plant invasions has been well-documented,
the impact of nutrient enrichment on fish invasions remains unexplored. In this study, field investigations were conducted to examine the impact
of nutrient enrichment on the maturity and reproduction of the invasive detritivorous fish Pterygoplichthys spp. A pair-wise greenhouse
experiment was carried out to test the impact of nutrient enrichment on the performance of Pterygoplichthys spp. and the native fish
Cirrhinus molitorella. Female Pterygoplichthys spp. matured at a larger size when total phosphorus concentration increased,
while mean size and age at maturity of males increased with an increase in total nitrogen. Furthermore, total phosphorus concentrations were
significantly lower when Pterygoplichthys spp. were present relative to those trials with C. molitorella. Eutrophication provides
empty niches, which may facilitate the invasion of non-native and hypoxia tolerant fish. Thus Pterygoplichthys spp. may adjust their
life-history traits to maximize fitness in eutrophic ecosystems. They might also benefit from nutrient enrichment due to their abilities
to utilize phosphorus. These adaptive responses may help this non-native hybrid swarm to colonize and spread in their introduced range.
These findings are instructive for understanding the relationship between biogeochemical changes and fish invasions, which will aid
in minimizing the risk of biological invasions when developing management strategies in polluted ecosystems. |
|