Developing a Statistically Valid AND Practically Useful Student Evaluation Instrument

The current article presents the findings on the development of a student evaluation instrument in which course evaluation is directly tied to student learning outcomes. With a committee consisting of instructors from six distinct disciplines brought together as part of a working group for this purpose, the instrument was developed utilizing research on the components of effective teaching and how these components impacted student learning. The instrument was tested at two time points, once via pen and paper (n=340 students) and the other online (n=2636 students). Factor Analysis resulted in one latent factor both times. The instrument also had high internal consistency reliability. Comparisons of individual student factors revealed a few variables significantly predicted ratings, but effect sizes were small. This work suggests an instrument has been created that assesses components of effective teaching, via the impact on student learning, and the ratings obtained are not highly influenced by individual factors

Drivers of octopus abundance and density in an anchialine lake: a 30 year comparison

Anchialine systems are isolated from the sea and often support species’ populations distinct from their marine counterparts. Sweetings Pond, an anchialine lake on the island of Eleuthera in The Bahamas was identified as a site of high Caribbean reef octopus, Octopus briareus (Robson, 1929) density, relative to coastal populations. However, observed deterioration in local benthic habitat and increased anthropogenic influence over the last 30 years imply that this octopus population may have undergone density and distribution shifts in response to these changing conditions. Here, we assess the system wide octopus density to provide an updated estimate. We hypothesize that despite depressed habitat availability in the 1980s, it will now support octopus densities less than historical estimates because of increasing human impact on the system. Drivers of abundance were also modelled, testing ecological hypotheses of the relationship between octopus count and prey, habitat coverage, and human disturbance. Octopus briareus were found in 7 of 27 of surveys with a mean survey count of 0.630 ± 1.25 per 900 m2. Octopus density did not vary significantly between sites. Octopus count was predicted to increase with increasing cover of calcareous rubble and the density of a preferred prey species, and intriguingly, counts decreased as a function of natural den abundance. System wide octopus density was comparable to earlier studies from the 1980s (1982 = 717.38 per km2; 1983 = 282.59 per km2; 2019 = 643.81 per km2) with no significant difference between years. Given the ecosystem’s unique and closed ecological community and the population dynamics and distribution drivers we present, Sweetings Pond has the potential to act as a ‘natural laboratory’ to explore further questions about marine insular systems and their influence on species populations in terms of ecological and behavioural change

An experimental assessment of social tolerance and den ecology in a high-density octopus population

Long held notions of the universally asocial octopus are being challenged due to the identification of high-density and interacting octopus populations in Australia, Indonesia, Japan and the deep sea. This study experimentally assessed the social tolerance and presence of potential prey items of Caribbean reef octopus, Octopus briareus, in a tropical marine lake (25°21′40″N, 76°30′40″W) on the island of Eleuthera, The Bahamas, by deploying artificial dens in multi-den groups or ‘units’ in the months of May and June 2019. Fifteen octopus were observed occupying dens (n = 100), resulting in 13 den units being occupied (n = 40). Two examples of adjacent occupation within a single den unit were identified but with zero examples of cohabitation/den sharing. Ecological models showed den and den unit occupation was predicted to increase with depth and differ between sites. Octopus also displayed no preference for isolated or communal units but preferred isolated dens over dens adjacent to others. Additionally, 47 % of occupied dens contained bivalve or crustacean items with no epifauna on their interior surface. The lack of epifauna suggests that these items have been recently ‘cleaned’ by occupying octopus and so represent likely prey. This study presents evidence of possible antisocial den use by O. briareus, a modification of the default ‘asocial’ ignoring of conspecifics typically attributed to octopus. This is likely in response to the high population density and may imply behavioural plasticity, making this system appropriate for further scrutiny as a research location on the influence of large, insular environments on marine species

Techniques used to increase recapture rates of dwarf seahorses (Hippocampus zosterae) in Tampa Bay: Implications for population estimates and movement patterns

Mark-recapture techniques were used to estimate population size and movement patterns of the Dwarf Seahorse (Hippocampus zosterae, Syngnathidae), a species native to the Gulf of Mexico and under review by the National Marine Fisheries Service (NMFS, USA) for consideration under the Endangered Species Act (ESA). Previous collection methods have failed to yield recapture rates high enough to use for population estimation, hypothesized to be a result of longer time durations between collections and large distances surveyed in previous studies. In this report, Dwarf Seahorses in Tampa Bay, Florida (USA) were sampled with a pushnet in a small, well-marked area (up to 40m2 per site) with more thorough and frequent resampling than previous studies. This change in the resampling resolution from earlier work increased recapture rates from 0.33% and 0.47% reported previously to 33% in the present study, demonstrating the importance of scale in sampling techniques. Increased recapture rates allowed for estimation of movement patterns, with similar movement distances and time intervals between sightings observed by sex; however, females were more likely than males to move between sites. Sex did not appear to influence recapture rates, with similar recapture rates between males and females. This project indicates that monitoring programs for the Dwarf Seahorse will need to be designed carefully as traditional sampling schemes used successfully for larger species of seahorses are unreliable or not feasible to use with smaller species

When more is not merrier: Using wild population dynamics to understand the effect of density on ex situ seahorse mating behaviors.

Seahorses are considered one of the most iconic examples of a monogamous species in the animal kingdom. This study investigates the relationship between stocking density and mating and competitive behavior from the context of the field biology of the dwarf seahorse, Hippocampus zosterae (Jordan & Gilbert). Animals were housed in 38 liter tanks at a range of densities and sex ratios (from 2-8 animals per tank), and their reproductive and other social behaviors were monitored from tank introduction through copulation. At low tank densities and even sex ratios but comparatively high field densities, frequency of both mating and competitive behaviors was low in trials. A higher level of males in tanks across all densities increased competition, activity levels, and aggression leading to egg transfer errors and brood expulsion, resulting in lower reproductive success. Across seahorse species, mean and maximum wild densities were consistently lower than those used in ex situ breeding, with adult sex ratios that were significantly female biased. However, significant variation exists in wild seahorse densities across species, with higher densities detected in focal/mark recapture studies and on artificial habitat structures than reported with belt transect sampling techniques. Interchange of knowledge gained in both aquarium and wild contexts will allow us to better understand the biology of this genus, and improve reproduction in captivity. Interpreting ex situ reproductive behaviors of seahorses within various densities reported from natural populations will help us predict the impact of conservation efforts and increase the likelihood of long-term persistence of populations for this threatened genus

Developing a Statistically Valid AND Practically Useful Student Evaluation Instrument

The current article presents the findings on the development of a student evaluation instrument in which course evaluation is directly tied to student learning outcomes. With a committee consisting of instructors from six distinct disciplines brought together as part of a working group for this purpose, the instrument was developed utilizing research on the components of effective teaching and how these components impacted student learning. The instrument was tested at two time points, once via pen and paper (n=340 students) and the other online (n=2636 students). Factor Analysis resulted in one latent factor both times. The instrument also had high internal consistency reliability. Comparisons of individual student factors revealed a few variables significantly predicted ratings, but effect sizes were small. This work suggests an instrument has been created that assesses components of effective teaching, via the impact on student learning, and the ratings obtained are not highly influenced by individual factors

An examination of the population dynamics of syngnathid fishes within Tampa Bay, Florida, USA

Seagrass ecosystems worldwide have been declining, leading to a decrease in associated fish populations, especially those with low mobility such as syngnathids (pipefish and seahorses). This two-year pilot study investigated seasonal patterns in density, growth, site fidelity, and population dynamics of Tampa Bay (FL) syngnathid fishes at a site adjacent to two marinas under construction. Using a modified mark-recapture technique, fish were collected periodically from three closely located sites that varied in seagrass species (Thalassia spp., Syringodium spp., and mixed-grass sites) and their distance from open water, but had consistent physical/chemical environmental characteristics. Fish were marked, photographed for body size and gender measurements, and released the same day at the capture site. Of the 5695 individuals surveyed, 49 individuals were recaptured, indicating a large, flexible population. Population density peaks were observed in July of both years, with low densities in late winter and late summer. Spatially, syngnathid densities were highest closest to the mouth of the bay and lowest near the shoreline. Seven species of syngnathid fishes were observed, and species-specific patterns of seagrass use emerged during the study. However, only two species, Syngnathus scovelli and Hippocampus zosterae, were observed at high frequencies. For these two species, body size decreased across the study period, but while S. scovelli's population density decreased, H. zosterae's increased. Across six of the seven species, population size declined over the course of this preliminary study; however, seasonal shifts were impossible to distinguish from potential anthropogenic effects of construction

Molecular Twister: A Game for Exploring Solution Chemistry

<p>pH is an essential biological concept with critical importance at various scales, from the molecular level, dealing with blood buffers, homeostasis, and proton gradients, all the way up to the ecosystem level, with soil chemistry and acid rain. However, pH is also a concept that spawns student misconceptions and misunderstanding in terms of what is happening in a solution on the atomic level. The Molecular Twister game, created for a Florida Department of Education funded professional development workshop for Florida high school teachers hosted at the University of Tampa  (Science Math Masters), seeks to model pH in such a way that students can visually and kinesthetically learn the concept in a few minutes. In addition, the basic design of the game pieces allow for teaching extensions to include more complex acid-base reactions. Challenge questions are provided to allow teachers to bring relevancy to the game, using examples of acid-base chemistry pulled from cases in human health and the environment.</p

An examination of the population dynamics of syngnathid fishes within Tampa Bay, Florida, USA

Seagrass ecosystems worldwide have been declining, leading to a decrease in associated fish populations, especially those with low mobility such as syngnathids (pipefish and seahorses). This two-year pilot study investigated seasonal patterns in density, growth, site fidelity, and population dynamics of Tampa Bay (FL) syngnathid fishes at a site adjacent to two marinas under construction. Using a modified mark-recapture technique, fish were collected periodically from three closely located sites that varied in seagrass species (Thalassia spp., Syringodium spp., and mixed-grass sites) and their distance from open water, but had consistent physical/chemical environmental characteristics. Fish were marked, photographed for body size and gender measurements, and released the same day at the capture site. Of the 5695 individuals surveyed, 49 individuals were recaptured, indicating a large, flexible population. Population density peaks were observed in July of both years, with low densities in late winter and late summer. Spatially, syngnathid densities were highest closest to the mouth of the bay and lowest near the shoreline. Seven species of syngnathid fishes were observed, and species-specific patterns of seagrass use emerged during the study. However, only two species, Syngnathus scovelli and Hippocampus zosterae, were observed at high frequencies. For these two species, body size decreased across the study period, but while S. scovelli's population density decreased, H. zosterae's increased. Across six of the seven species, population size declined over the course of this preliminary study; however, seasonal shifts were impossible to distinguish from potential anthropogenic effects of construction