We studied the feeding ecology of juvenile loggerhead turtles Caretta caretta in the western Mediterranean based on the contents of the digestive tract of 54 turtles (range of CCL: 34±69 cm) seized in Barcelona (Spain) in 1991. Turtles had been captured in ®shing trawls, but speci®c information about dates and localities is not available. Despite this limitation, we obtained interesting evidences about the foraging strategies of loggerheads, with potentially important conservation implications. We report 33 new taxa in the diet. Results indicated that western Mediterranean loggerheads feed in an opportunistic way. Numerically, ®sh made up the most important prey group, followed by pelagic tunicates, crustaceans, molluscs and other invertebrates. The importance of ®sh as a food resource has been rarely reported, and several lines of evidence indicated that ®sh were possibly consumed as discarded by-catch. This raises the question over whether or not western Mediterranean ®sheries are an important food source for juvenile loggerheads. The number and diversity of prey increased with turtle size, this may re¯ect the lack of prey selectivity of juvenile loggerheads coupled with a higher retention of food remains in larger turtles. Discounting prey that could be consumed as discarded by-catch, dietary data suggest that most, if not all, loggerheads of our sample were captured in neritic habitats. However, many turtles contained remains of both pelagic and benthic-demersal prey. These observations support the existence of an intermediate neritic phase in loggerheads' developmental shift from pelagic±oceanic to benthic±neritic foraging habitats, as previously suggested. During this phase, loggerheads would feed upon both pelagic and benthic prey.

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If Dark Matter is made of Weakly Interacting Massive Particles (WIMPs) with masses below GeV, the corresponding nuclear recoils in mainstream WIMP experiments are of energies too close, or below, the experimental threshold. Gas Time Projection Chambers (TPCs) can be operated with a variety of target elements, offer good tracking capabilities and, on account of the amplification in gas, very low thresholds are achievable. Recent advances in electronics and in novel radiopure TPC readouts, especially micro-mesh gas structure (Micromegas), are improving the scalability and low-background prospects of gaseous TPCs. Here we present TREX-DM, a prototype to test the concept of a Micromegas-based TPC to search for low-mass WIMPs. The detector is designed to host an active mass of  kg of Ar at 10 bar, or alternatively kg of Ne at 10 bar, with an energy threshold below 0.4 keVee, and is fully built with radiopure materials. We will describe the detector in detail, the results from the commissioning phase on surface, as well as a preliminary background model. The anticipated sensitivity of this technique may go beyond current experimental limits for WIMPs of masses of 2–8 GeV.