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The 2007-08 Annual Report presents and analyzes the performance of students in Nebraska Reading First schools during the 2007-08 school year. Teacher log information is also presented, and a district performance comparison is made from the year just previous to Reading First implementation across the four years of implementation. [This report was published by the Great Plains Institute for Reading and Writing, College of Education and Human Sciences, University of Nebraska-Lincoln.]

Copepods of the genus Calanus dominate the biomass of pelagic ecosystems from the Mediterranean Sea up into the Arctic Ocean and form an important link between phytoplankton and higher trophic levels. Impacts from toxin-producing harmful algae (HA) have been recorded throughout this region over the last 50 years, with potentially negative effects on Calanus spp. populations and the ecosystem functions and services they provide. Here we examine how ingestion, egg-production and egg-viability in Calanus helgolandicus are affected by the relative abundance of the toxin-producing dinoflagellate Alexandrium catenella in their diet. Our four-day experiments demonstrate that the ingestion rate of C. helgolandicus declined significantly as the percentage of toxin-producing A. catenella within their diet increased, whereas egg production and egg viability were unaffected. Toxin profile concentrations for A. catenella are presented alongside body toxin-loads in C. helgolandicus after 4 days of feeding on these cells. The body toxin concentrations of C. helgolandicus were 3.6–356.6 pg STX diHCl eq. copepod−1, approximately 0.02–3.3 % of the toxins ingested. Our work suggests that the effects of exposure to A. catenella may be negligible in the short-term but could manifest if bloom conditions persist for longer than our experimental duration.

This study investigated impacts of the algal toxin domoic acid (DA) on copepods in Scottish waters. Inspection of seasonal patterns revealed that several common copepods (Acartia spp. Dana, 1846, Calanus spp. Leach, 1816, Centropages spp. Krøyer, 1849, Pseudocalanus spp. Boeck, 1872, and Temora longicornis (Müller O.F., 1785)) regularly coexist with potentially toxic species from the diatom genus Pseudo-nitzschia H. Peragallo in H. Peragallo and M Peragallo, 1900. A short field study investigating the DA content of Calanus spp. at the Scottish Coastal Observatory site at Stonehaven recorded DA during every sampling event. The highest DA levels were associated with a July bloom (∼135000 cells L−1) of Pseudo-nitzschia cf. plurisecta Orive & Pérez-Aicua 2013. Several studies have previously investigated effects of ingested DA on copepods but information on effects of dissolved DA is lacking, therefore, simple exposure experiments were carried out to measure mortality of copepod species at ecologically relevant concentrations of dissolved DA. The highest concentrations tested (≥ 50 ng DA mL−1) decreased survival in Temora longicornis only; survival of other copepod species was unaffected. However, T. longicornis feeding on non-toxic algae in the presence of dissolved DA did not accumulate DA in their tissue. This study provides evidence of the potential for Calanus spp. to act as vectors for DA to higher trophic levels in Scottish waters.

Calanoid copepods comprise around 90% of Arctic zooplankton biomass and are fundamental to the ecological and biogeochemical functioning of high-latitude pelagic ecosystems. They accumulate lipid reserves during the productive months and represent an energy-rich food source for higher trophic levels. Rapidly changing climate in the Arctic may alter the quantity and composition of the food environment for one of the key copepod species, Calanus finmarchicus, with as yet unquantified effects on its production. Here we present rates of feeding and egg production in female C. finmarchicus exposed to the range of feeding conditions encountered across the Fram Strait in May/June 2018. Carbon (C) budgets were constructed and used to examine the relationship between feeding and growth (= egg production) in these animals. C-specific ingestion rates (mean ± standard deviation) were highly variable, ranging from 0.015 ± 0.004 to 0.645 ± 0.017 day-1 (mean = 0.295 ± 0.223 day-1), and were positively correlated with food availability. C-specific egg production rates ranged from 0.00 to 0.049 day-1 (mean = 0.012 ± 0.011) and were not correlated with either food availability or ingestion rate. Calculated gross growth efficiencies (GGE: growth/ingestion) were low, 0.12 ± 0.13 (range = 0.01 to 0.39). The assembled C budgets indicate that the average fraction of ingested food that was surplus to the requirements for egg production, respiration and losses to faecal pellets was 0.17 ± 0.42. We suggest that this excess occurred, at least in part, because many of the incubated females were still undergoing the energetically (C-) expensive process of gonad maturation at the time of sampling, an assertion that is supported by the relatively high C:N (nitrogen) ratios of the incubated females, the typically low egg production rates, and gonad maturation status. Ontogenetic development may thus explain the large variability seen in the relationship between egg production and ingestion. The ap