Trait Variation in an Everglades Invasive Species: Life histories, Boldness, and Dispersal in the African Jewelfish

Abstract Traits that aid in the invasion process should exhibit a gradient across the expansion range in response to changing selection pressures. Aggression has been repeatedly associated with invasion success in many taxa, as it may help invaders to wrestle the resources from other species which enhances their success in a novel environment. However, aggression primarily allows individuals to overcome conspecific rivals, providing advantages in competition over resources. Agonistic prowess could therefore increase fitness at both ends of the expansion gradient. Here we review the role of aggression in range expansion of invasive species, and its potential role as a driver of range expansion. We analyze how these different mechanisms could affect trait variation in expanding and invasive populations. Specifically, we look at how aggression could help dilate the edges of a population through niche competition, as well as lead to exclusion from the center (i.e. areas of high population density) by the conspe-cifics. Both of these processes will result in a characteristic spatial distribution of phenotypes related to aggression that could provide insights into the ecological pressures and dynamics of expanding populations, potentially providing clues to their success as niche competitors and invasive species.

Download Full-text

Invasive traits of veronicellid slugs in the Hawaiian Islands and temperature response suggesting possible range shifts under a changing climate

Journal of Molluscan Studies ◽

10.1093/mollus/eyz042 ◽

2020 ◽

Vol 86 (2) ◽

pp. 147-155

Author(s):

Rachel M Sommer ◽

Robert H Cowie

Keyword(s):

Invasive Species ◽

Life Histories ◽

Temperature Response ◽

Egg Mass ◽

Warming Climate ◽

Self Fertilization ◽

Single Mating ◽

The Mean ◽

Mass Mating ◽

Growth And Reproduction

Abstract Understanding life history traits is important for assessing potential invasiveness, particularly in the context of the future spread of invasive species under climate change. A number of species of Veronicellidae have been introduced beyond their native ranges and have become invasive. Two of these species, Veronicella cubensis and Laevicaulis alte, are widespread in Hawaii, yet little is known of their life histories. This study of growth and reproduction and their relation to temperature in these two species was undertaken using laboratory stocks derived from individuals collected in Hawaii. More data were collected for V. cubensis than for L. alte because of difficulty maintaining the latter in the lab. Veronicella cubensis grew faster at 22 °C than at 27 °C. At 22 °C, the mean age at which V. cubensis first mated was 203 d, and the mean age when eggs were first laid was 226 d. Mating in V. cubensis lasted more than a day, and it took up to 4 d to lay an egg mass. Mating took less than a day in L. alte. No self-fertilization was recorded in V. cubensis, but a single L. alte individual maintained alone from hatching laid fertilized eggs. Sperm storage after a single mating in V. cubensis was estimated to last up to 6 months. In both species the time for eggs to hatch was shorter at 27 °C than at 22 °C. Hatchability was between 74 and 93%. Veronicella cubensis lived for at least 2 years and was estimated to produce at least 400 eggs over its life. Climate warming will probably lead to expansion of the ranges of V. cubensis and L. alte to higher elevations in Hawaii and elsewhere. Growth and reproduction will also be affected by a warming climate and therefore impact the success of these invasive species.

Download Full-text

Genetic basis of adult migration timing in anadromous steelhead discovered through multivariate association testing

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.3064 ◽

2016 ◽

Vol 283 (1830) ◽

pp. 20153064 ◽

Cited By ~ 66

Author(s):

Jon E. Hess ◽

Joseph S. Zendt ◽

Amanda R. Matala ◽

Shawn R. Narum

Keyword(s):

Life Histories ◽

Multivariate Analyses ◽

Learning Algorithm ◽

Association Studies ◽

Mixed Linear Model ◽

Major Effect ◽

Candidate Snps ◽

Nucleotide Polymorphisms ◽

Trait Variation ◽

Migration Timing

Migration traits are presumed to be complex and to involve interaction among multiple genes. We used both univariate analyses and a multivariate random forest (RF) machine learning algorithm to conduct association mapping of 15 239 single nucleotide polymorphisms (SNPs) for adult migration-timing phenotype in steelhead ( Oncorhynchus mykiss ). Our study focused on a model natural population of steelhead that exhibits two distinct migration-timing life histories with high levels of admixture in nature. Neutral divergence was limited between fish exhibiting summer- and winter-run migration owing to high levels of interbreeding, but a univariate mixed linear model found three SNPs from a major effect gene to be significantly associated with migration timing ( p < 0.000005) that explained 46% of trait variation. Alignment to the annotated Salmo salar genome provided evidence that all three SNPs localize within a 46 kb region overlapping GREB1-like (an oestrogen target gene) on chromosome Ssa03. Additionally, multivariate analyses with RF identified that these three SNPs plus 15 additional SNPs explained up to 60% of trait variation. These candidate SNPs may provide the ability to predict adult migration timing of steelhead to facilitate conservation management of this species, and this study demonstrates the benefit of multivariate analyses for association studies.

Download Full-text

Life Histories and Other Biological Characteristics Enabling the Establishment of Aedes albopictus in the San Gabriel Valley, California

Journal of the American Mosquito Control Association ◽

10.2987/17-6699.1 ◽

2018 ◽

Vol 34 (2) ◽

pp. 93-98 ◽

Cited By ~ 1

Author(s):

Gimena Ruedas ◽

Hendricks Peña ◽

Angela Brisco ◽

Kenn K. Fujioka ◽

J. Wakoli Wekesa

Keyword(s):

Invasive Species ◽

Vector Control ◽

Larval Development ◽

Aedes Albopictus ◽

Environmental Conditions ◽

Life Histories ◽

Biological Characteristics ◽

Egg Hatching ◽

Ecological Conditions ◽

San Gabriel Valley

ABSTRACT Since Aedes albopictus was discovered in 2011 in the San Gabriel Valley it has become widespread despite the “harsh” environmental conditions and intense efforts to control or eliminate it. Species introduced into a new area may survive, thrive, or disappear depending on whether its new environment is suitable. The San Gabriel Valley Mosquito and Vector Control District expended considerable resources from 2011 to 2015 to eradicate this invasive species or, at a minimum, control and manage its spread. Despite the intense effort, the distribution of Ae. albopictus steadily expanded. Over those 5 years this increase shifted from a geometric to exponential pattern. What enabled Ae. albopictus to survive initially, become established, and then expand their distribution when ecological conditions in southern California were considered hostile for this invasive species? This study explores several biological characteristics including skip oviposition, installment egg hatching, and variable larval development that may have helped Ae. albopictus flourish in its new environment.

Download Full-text

Ecological significance of some kenophytes in Lower Silesian national parks

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2008.021 ◽

2011 ◽

Vol 77 (2) ◽

pp. 167-174 ◽

Cited By ~ 1

Author(s):

Jerzy Fabiszewski ◽

Teresa Brej

Keyword(s):

Invasive Species ◽

National Parks ◽

Life Histories ◽

Biological Diversity ◽

Vegetative Reproduction ◽

Mountain Forest ◽

Annual Increment ◽

Impatiens Glandulifera ◽

Reynoutria Japonica ◽

Reproduction Strategies

The paper presents the results of several years investigations (2003-2007) on two invaders: the Himalayans Impatiens glandulifera and Asiatic Reynoutria japonica. The Sudety Mountains and their national parks are under strong pressure of both species, threatening the local vegetation. The four-year investigations have been carried out in field, glasshouse and in laboratory. Invasive species have their peculiar life histories which help them to occupy new areas. Those are above all the specific generative reproduction strategies (Impatiens) or vegetative reproduction strategies (Reynoutria). Both strategies secure the reproductive success and to capture more and more highly situated areas of the mountains. Very significant characteristics connected with the expansion of invaders is the excessively over and above the average production of seeds (Impatiens) and a huge annual increment aboveground biomass (Reynoutria). The investigated invasive species are probably not equipped with influence of allelopatic type as of greater importance is their competitive strength. The invaders can eliminate a part of the early spring flora belonging to the geophyte group and impoverish the regional biological diversity. Both the invasive plants enter also into some moist mountain forest communities.

Download Full-text

Geographic patterns of seed trait variation in an invasive species: how much can close populations differ?

Oecologia ◽

10.1007/s00442-021-04971-2 ◽

2021 ◽

Author(s):

Erola Fenollosa ◽

Laia Jené ◽

Sergi Munné-Bosch

Keyword(s):

Invasive Species ◽

Seed Production ◽

Anthropogenic Pressure ◽

Seed Traits ◽

Trait Variation ◽

Interpopulation Variability ◽

Seed Trait ◽

Bioclimatic Variables ◽

Human Density ◽

Trait Variability

AbstractSeeds play a major role in plant species persistence and expansion, and therefore they are essential when modeling species dynamics. However, homogeneity in seed traits is generally assumed, underestimating intraspecific trait variability across the geographic space, which might bias species success models. The aim of this study was to evaluate the existence and consequences of interpopulation variability in seed traits of the invasive species Carpobrotus edulis at different geographical scales. We measured seed production, morphology, vigour and longevity of nine populations of C. edulis along the Catalan coast (NE Spain) from three differentiated zones with a human presence gradient. Geographic distances between populations were contrasted against individual and multivariate trait distances to explore trait variation along the territory, evaluating the role of bioclimatic variables and human density of the different zones. The analysis revealed high interpopulation variability that was not explained by geographic distance, as regardless of the little distance between some populations (< 0.5 km), significant differences were found in several seed traits. Seed production, germination, and persistence traits showed the strongest spatial variability up to 6000% of percent trait variability between populations, leading to differentiated C. edulis soil seed bank dynamics at small distances, which may demand differentiated strategies for a cost-effective species management. Seed trait variability was influenced by human density but also bioclimatic conditions, suggesting a potential impact of increased anthropogenic pressure and climate shifts. Geographic interpopulation trait variation should be included in ecological models and will be important for assessing species responses to environmental heterogeneity and change.

Download Full-text