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Frontaura, E. R.

Publications and source records attributed to Frontaura, E. R..

2 recordsLinked to original sources

Colour preference in juvenile European lobster (Homarus gammarus)

Lobsters are high-value marine-fished species, and re-stocking efforts are essential for replenishing depleted wild populations and ensuring the longevity of these valuable marine species. The need for stock enhancement and hatcheries for aquaculture is vital to reduce the strain on wild populations. Therefore, environmental colours should be acknowledged when rearing lobsters in terms of behaviour, growth, movement, and survival. However, the behavioural effects the surrounding colour poses are virtually unknown. To better understand this behaviour, the movement of juvenile European lobsters (Homarus gammarus) was analysed through videos in two sub-trials. Lobsters were acclimated to custom-made alternating colour chambers, allowing for colour preferences based on individual movement. Sub-trial one alternated between black, red, blue, green, white, and yellow. The study identified that there was a significant preference for black (1 hour and 51 minutes) and red (1 hour and 33 minutes), indicating a potential underlying benefit for juvenile H. gammarus development. Despite this, little is known about the overall association of colour and lobster perception. A better understanding of environmental colour preference may guide the construction of aquaculture units to suit colour preference and enhance acclimation into newly released environments. This experiment aims to determine the preferred colours of stage four juvenile H. gammarus in a controlled laboratory setting and inspire further research to explore this unfamiliar field.

animal behavior and cognition↗

Influence of pseudo-green water on growth, colouration, and survival in European lobster (Homarus gammarus) larvae

With the depletion of European lobster (Homarus gammarus) wild stocks from historic overexploitation, the attention has turned towards restocking, stock enhancement programs and farming potential. The early life larval stages of the European lobster present a major barrier to hatchery production efforts due to low survival rates. Green water techniques are rapidly growing due to their ability to improve nutrition quality. This study explores the potential benefits of using pseudo-green water. This is determined by adding microalgae to the rearing environment of larvae by analysing the effects on growth and survival. The commonly used algal species: Tetraselmis suecica (TS), Dunaliella salina (DS), and Nannochloropsis sp. (N) were added as monoculture or mixture treatments to a controlled European lobster larvae-rearing environment over thirteen days. The trial consisted of seven permutations of algal treatments (TS, DS, N, TS+DS, TS+N, DS+N, and TS+DS+N) and one control group, with clear water conditions using length measurements, survival rates and colouration to determine treatment impacts at the end of the trial. Results indicate that mixtures of algal species outperformed monocultures and clear water regarding growth performance. Nannochloropsis sp. is of significant benefit to growth performance. Algal mixes containing Nannochloropsis sp. resulted in significantly better growth than D. salina monoculture treatment. There were no significant differences in survival rates between treatment groups.

developmental biology↗