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Marine ornamental aquaculture is a growing industry. Although most species are cultured for aesthetic purposes, there is increasing interest in organisms that provide functional services. Nudibranchs provide an example in which they act as biological controls by consuming aquaria pests. Berghia stephanieae is a commercially relevant nudibranch that feeds on Exaiptasia anemones, which overgrow sessile invertebrates. However, information pertaining to B. stephanieae feeding habits remains unaddressed. Therefore, this study investigated the following: (a) the effect of feeding frequency on fecundity, (b) optimum prey size, (c) the ability to feed on prey fragments, and (d) the influence of intraspecific competition. Distinct feeding frequencies were tested and embryos produced were quantified; growth of nudibranchs offered different anemone sizes was measured; whole and fragmented anemones were offered, with preference recorded; and growth and mortality of juvenile nudibranchs were recorded in the absence and presence of adult conspecifics. Results show that feeding daily produced the highest number of embryos. Juveniles fed on medium‐sized anemones showed the highest growth rate. Smaller juveniles were unable to feed on whole anemones and preferred fragmented anemones. Juvenile growth and survival decreased in the presence of adults. To maximize production, breeders must feed broodstock daily, provide medium‐sized anemones or fragments, and segregate juveniles from adults.

<p>The Paris Agreement long-term temperature goal (Paris Agreement LTTG) aims to limit global warming to well below 2ºC, if possible to a maximum of 1.5ºC. To understand how this goal could be accomplished, idealized scenarios have been explored in the past years, with a special focus on pathways for reaching net-zero CO<sub>2</sub> emissions. </p> <p>Non-CO<sub>2</sub> forcing is, however, known to contribute to a decrease in the remaining carbon budgets related to the Paris Agreement LTTG (e.g., Mengis & Matthews, 2020). A full picture regarding this benchmark can therefore only be painted when including the effects of aerosols, non-CO<sub>2</sub> greenhouse gases and land use changes. These forcings along with the zero emissions commitment to CO<sub>2</sub> will define whether temperature is able to stabilize once CO<sub>2</sub> emissions decrease.  </p> <p>To explore individual effects from anthropogenic non-CO<sub>2</sub> forcing agents, their respective contributions to the Paris Agreement LTTG scenarios (Rogelj, et al., 2019) is estimated and put into relation. We will present results primarily on the impacts of aerosols and land use change representation as well as their effects on the carbon cycle and climate by simulating LTTG scenarios using an Earth system model of intermediate complexity (UVic ESCM, version 2.10, Mengis et al., 2020). The climate response in these all forcing net-zero CO<sub>2</sub> emission scenarios will provide us with relevant insights concerning allowable emissions for temperature stabilization.</p> <p><strong>References: </strong></p> <p>Mengis, N., Matthews, H.D. Non-CO<sub>2</sub> forcing changes will likely decrease the remaining carbon budget for 1.5 °C. <em>npj Clim Atmos Sci</em> <strong>3</strong>, 19 (2020). https://doi.org/10.1038/s41612-020-0123-3</p> <p>Mengis, N., Keller, D. P., MacDougall, A. H. <em>et al.</em> Evaluation of the University of Victoria Earth System Climate Model version 2.10 (UVic ESCM 2.10). <em>Geosci. Model Dev.</em> <strong>13</strong>, 4183–4204 (2020). https://doi.org/10.5194/gmd-13-4183-2020  </p> <p>Rogelj, J., Huppmann, D., Krey, V. <em>et al.</em> A new scenario logic for the Paris Agreement long-term temperature goal. <em>Nature</em> <strong>573</strong>, 357–363 (2019). https://doi.org/10.1038/s41586-019-1541-4</p>

<p>In scenarios with abrupt cessation of CO<sub>2</sub> emissions (ZECMIP) the committed warming is expected to be 0±0.3K [1]. It is imperative to understand and narrow this uncertainty range because it is similar in size to the remaining allowable warming until 1.5K. We have shown that temperature changes up to 3K are present at regional scales [2]. Furthermore significant differences between models are observed which are important to understand the uncertainties in the zero emissions committed warming.</p> <p>Analysing the ZECMIP simulations of nine ESMs, we identify common climate patterns and notable differences in an idealised zero CO<sub>2 </sub>emissions scenario. We distinguish between patterns within and outside of natural model climate variability, and will present first results for likely causes in commonalities linked to ocean circulations and predominant climate modes.</p> <p> </p> <p>References:</p> <p>[1] A. H. MacDougall et al., <em>Is There Warming in the Pipeline? A Multi-Model Analysis of the Zero Emissions Commitment from CO</em><em><sub>2</sub></em>, Biogeosciences <strong>17</strong>, 2987 (2020).</p> <p>[2] A. H. MacDougall, J. Mallett, D. Hohn, and N. Mengis, <em>Substantial Regional Climate Change Expected Following Cessation of CO</em><em><sub>2</sub></em><em> Emissions</em>, Environmental Research Letters <strong>17</strong>, 114046 (2022).</p>