Temporal and spatial variability of an invasive toxigenic protist in a North American subtropical reservoir

Hambright, K. David; Zamor, Richard M.; Easton, James D.; Glenn, Karen L.; Remmel, Emily J.; Easton, Anne C.

doi:10.1016/j.hal.2010.04.006

Cited by 46 publications

(43 citation statements)

References 29 publications

(28 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this reservoir, winter blooms of P. parvum have occurred almost yearly since 2003, but only in the western arm of the reservoir, characterized by relatively high salinities (28,29). Although still presumably subjected to downstream transport of propagules from these large, sustained blooms, which can reach densities over 2 × 10 5 cells per mL, the rest of the lake has not experienced any establishment of P. parvum (defined as recurrent winter blooms).…”

Section: Discussionmentioning

confidence: 99%

“…Experiments were conducted with natural freshwater microbial communities in microcosms. Samples from surface waters of three sites in Lake Texoma (sampling stations: L2, frequent winter P. parvum blooms; L4, P. parvum present in winter; and L6, P. parvum rarely observed) (28) were retrieved, prefiltered with a 63-μm mesh to remove large zooplankton, mixed, and distributed into 21 2.5-L experimental microcosms. The absence (here defined as below the detection limit of 200 cells per mL) of P. parvum was confirmed by counting 10 hemocytometer fields at 200× magnification.…”

Section: Methodsmentioning

confidence: 99%

“…However, there are several recent observational (27)(28)(29) and experimental field studies (30,31) examining the potential roles of immigration and nutrient availability in population dynamics and impacts of P. parvum. Although they provide good first steps in addressing the recent P. parvum range expansion, these earlier studies are limited in design.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Dynamics of an experimental microbial invasion

Acosta

Zamor

Najar

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

The ecological dynamics underlying species invasions have been a major focus of research in macroorganisms for the last five decades. However, we still know little about the processes behind invasion by unicellular organisms. To expand our knowledge of microbial invasions, we studied the roles of propagule pressure, nutrient supply, and biotic resistance in the invasion success of a freshwater invasive alga, Prymnesium parvum, using microcosms containing natural freshwater microbial assemblages. Microcosms were subjected to a factorial design with two levels of nutrient-induced diversity and three levels of propagule pressure, and incubated for 7 d, during which P. parvum densities and microbial community composition were tracked. Successful invasion occurred in microcosms receiving high propagule pressure whereas nutrients or community diversity played no role in invasion success. Invaded communities experienced distinctive changes in composition compared with communities where the invasion was unsuccessful. Successfully invaded microbial communities had an increased abundance of fungi and ciliates, and decreased abundances of diatoms and cercozoans. Many of these changes mirrored the microbial community changes detected during a natural P. parvum bloom in the source system. This role of propagule pressure is particularly relevant for P. parvum in the reservoirdominated southern United States because this species can form large, sustained blooms that can generate intense propagule pressures for downstream sites. Human impact and global climate change are currently causing widespread environmental changes in most southern US freshwater systems that may facilitate P. parvum establishment and, when coupled with strong propagule pressure, could put many more systems at risk for invasion. microbial ecology | diversity | invasion resistance | propagule pressure | Prymnesium

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Dynamics of an experimental microbial invasion

Acosta

Zamor

Najar

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Roelke et al (2010) report that golden algae blooms have occurred frequently in Lake Whitney, Texas, and not in nearby Lake Waco despite similar nitrogen and phosphorus levels. Hambright et al (2010) similarly report that blooms and/or fish kills in Lake Texoma have occurred despite high phosphate ([0.1 mg/l) and high nitrate ([0.5 mg/l) levels. Eutrophication does not appear to cause golden algaerelated fish kills because golden algae blooms occur from mid-winter through spring, whereas nutrient-driven blooms tend to occur from late summer through early fall (W.J.…”

Section: Introductionmentioning

confidence: 94%

Atrazine selects for ichthyotoxic Prymnesium parvum, a possible explanation for golden algae blooms in lakes of Texas, USA

Yates

Rogers

2011

Ecotoxicology

View full text Add to dashboard Cite

Prymnesium parvum Carter is a mixotrophic haptophyte which, under certain environmental conditions, produces potent toxins responsible for fish kills around the world since the 1930s. Many P. parvum blooms have occurred in catchments where crop agriculture is a dominant land use; however, the effects of herbicides on bloom dynamics have not yet been investigated. Aquatic microbial communities containing P. parvum were subjected to two separate experiments involving the addition of either atrazine or glyphosate at varying concentrations. After 14, 21, and 28 days at 10 μg/l atrazine we observed that the relative abundance of P. parvum was significantly higher compared to the control. After 28 days, the relative abundance of P. parvum was approximately 53% higher in 10 μg/l atrazine compared to the control. Glyphosate exhibited no statistically-significant effect on the relative abundance of P. parvum. Inadequate characterization of the microbial community and uncertainty due to ecological and allelopathic effects of P. parvum made it difficult to establish strong relationships between herbicide sensitivity and nutritional mode. Large volumes of mobile and persistent herbicides with high toxicity to phytoplankton are used in cotton defoliation in Texas prior to the typical P. parvum pre-bloom period. These results have important implications for management, such as whether reduction in herbicide runoff could decrease the frequency and duration of P. parvum blooms in the future.

show abstract

“…A mixotrophic haptophyte, P. parvum has caused numerous harmful blooms worldwide (see Grané li et al, 2012) and in recent years has expanded to southern regions of the USA and as far north as Pennsylvania and West Virginia (Sager et al, 2008;Hambright et al, 2010;Roelke et al, 2011;Brooks et al, 2011b). P. parvum produces toxins that are lethal to gill breathing organisms, causing a change in the selective permeability of gill epithelial cells, thus inhibiting respiration.…”

Section: Introductionmentioning

confidence: 99%