674 Broom 13 Welfare invertebrates

Pre-publication copy 1 Broom, D.M. 2013. The welfare of invertebrate animals such as insects, spiders, 2 snails and worms. In Animal Suffering: From Science to Law, International 3 Symposium, ed. Kemp, T. A. van der and Lachance, M., 135-152. Paris: Éditions 4 Yvon Blais. 5 THE WELFARE OF INVERTEBRATE ANIMALS SUCH AS INSECTS, 6 SPIDERS, SNAILS AND WORMS 7 8 D. M. Broom 9 10 ABSTRACT 11 The concept of welfare applies to all animals but not to plants or inanimate objects. 12 Hence we can evaluate and discuss the welfare of invertebrate animals such as snails, 13 insects, spiders and worms, but this does not mean that they have all of the 14 capabilities of more complex animals, or that we wish to protect them in the same 15 way. In considering how we treat animals, one key question is “Should we respect 16 the life of this animal?” A second, linked question is “Should we consider the needs 17 of the animal if we interfere with its life?” A third is “Should we use anaesthetics and 18 analgesics if we damage the tissues of this animal?” There are further questions 19 about the level of awareness that the animal has. For many people, the answers to the 20 questions are affected by whether or not the animal is perceived to be a food item, or 21 likely to harm humans or their resources, or to be considered a beautiful living being. 22 However, when a limpet, a swimming nudibranch, a butterfly, a honeybee, a jumping 23 spider, or a phyllodocid worm is considered objectively, many people would answer 24 yes to two or more of the questions. Information about the various aspects of 25 sentience: perceptual ability, systems for pain and other feelings, learning ability, and 26 various indicators of cognition and awareness is relevant to decisions about 27 protection of animals. The concepts, and some evidence concerning these qualities in 28 invertebrate animals, are presented here. The invertebrate groups most likely to be 29 considered sentient, other than cephalopod molluscs and decapod Crustacea which 30 are reviewed in other papers, are discussed. Whilst cognitive ability in some spiders 31 is high and that in bees, ants and some gastropods is quite high, we cannot be sure 32 that any of these animals feel pain, or that they do not. There is a case for some 33 degree of protection for spiders, gastropods and insects. However, the case is not as 34 strong as that for vertebrates, cephalopods and decapod Crustacea at present. 35