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NOTE TO USERS This reproduction is the best copy available. The naîural history of ButhypoZyppus arcticus (Prosch), a deep-sea octopus. by James B. Wood Submitted in partial fdfdhent of the requirements for the degree of Doctor of PhiIosophy DaIhousie University Hahhq Nova Scotia April2000 O Copyright by James B. Wood, 2000 National Library Bibliothèque nationale I+I,canada du Canada Acquisitions and Acquisitions et Bibiiographic Services services bibliographiques 395 Wellington Street 395. rue Wellington Ottawa ON K1A ON4 Ottawa ON KIA ON4 Canada Canada Your file Votre r8fërence Our fi& Notre raférence The author has granted a non- L'auteur a accordé une licence non exclusive Licence allowing the exclusive permettant à la National Library of Canada to Bibliothéque nationale du Canada de reproduce, Ioan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microfom, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/^, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts f?om it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. Dedicated to Deborah and David Wood and In memory of Mi. J. Gregory Table of contents List of figures and tables ............................................... vü Abstract ............................................................ xi List of abbreviations and symbois wd..................................... W Achowledgments ................................................... xiii Prefàce ........................................................... xiv Chapter1.Introduction ................................................. 1 Cephalopodar Past and Present ................................... 2 Rearing and studying natural bistory of octopuses: confounding fhctors ... 12 Bathypolypus arcticus: A mode1 for deep-sea octopuses ............... 14 Chapter 2 . First growth rates of deep sea octopus Bathypolpus arcticus on fivediets ................................................. 29 Abstract ................................................... 30 Introduction ................................................ 31 Materialsandmethods ........................................ 37 Results ....................................................44 Discussion ................................................. 52 Chapter 3 .Rearing deep-sea octopus (Bathpolpus arcticus) at temperatures fkom2-10°C ..............................................63 Abstract ................................................... 64 Introduction ................................................ 65 Materials and methods ........................................ 67 Reds ....................................................74 Discussion ................................................. 83 Conclusions ................................................ 94 Chapter 4. Reproduction and embryonic development time of Bafhpolypus arcticus. a deep-sea octopod (Cephalopoda: Octopoda) .............. 95 Abstract ................................................... 96 Introduction ................................................ 97 Methods ................................................... 98 Results ................................................... 102 Discussion ................................................ 109 Chapter 5 .Do larger cephalopods live longer? The effects of temperature and phylogeny on interspecific comparisons of age and size at rnatunty ..... 115 Abstract .................................................. 116 Introduction ............................................... 117 Materials and methods ....................................... 120 Redts ................................................... 133 Discussion and concIusions ................................... 134 Chapter 6. Summary of results .......................................... 146 Su- ofnew contriibutions of this thesis ....................... 147 Summary and cornparison ofthe life cycle and ecology of B. mcticus .... 149 Final thoughts on size at ma* and temperature .................. 156 Futuredlrdons ........................................... 156 Technical Note 1 .Does weighmg stress affect the growth rate of octopuses? ....... 162 Technical Note 2. First growth data and prey choice for a coM water octopus. ButhypoZypt(s mcticus ................................. 175 Appendix 1 . Cephalopod predators ..... ,. ............................... 182 AppendSc 2. Cephalopod prey .......................................... 193 Appendix 3 . Cephalopod specimens donated to museum collections ............. 217 Appdîx 4 . Growth rates of hatchlnig BathypoZypus arcticus fed fie differentfoods ........................................... 222 Appendix 5 . Bathypolypus mctiais growth at three different temperatures ........ 238 Appendk 6. Cdculations used in Chapter 5 ................................ 241 Appendix 7 . Does Bathypolpus arcticus contain antiikeeze? ................... 248 References ......................................................... 249 List of figures and tables Chapter 1 Figures: Fig. 1. Age at maturity in years for three classes of molluscs ..................... 6 Fig. 2. This aduit wiki octopus (Octopbrimeus) was out hunting at night in theDryTortugasNationalParkinthe~ondaKeys ..................... 10 Fig. 3. The large, weIl developed eggs of Octops briorem are shown above ........ 11 Fig, 4. Hatchling deep-sea octopus, Bafhypolypusmcticz~s ..................... 15 Fig. 5. Average yield per tow of B. arcticus at various depths based on 486 tows done during 5 scallop assessrnent cruises in 1995 and 1996 ........... 17 Fig. 6. Number of octopuses found m tows over different bottom types. Raw data from Peter Auster. This initiaIly suppfied evidence that B. arcticus is found on mud and sand bottoms .................................. 18 Fig. 7. AU octopuses m Peter Amer's data sets were collected over sand or mud bottoms, although these were also the deepest tows. Thus the preferred bottom type of B. arcticus is still uncertaia The numbers to the right of the dark circles indicate the number of octopuses captured in the tow. Open circles represent tows where no octopuses were captured ............ 19 Tables: Table 1. Taxonomy in the WyOctopodidae following Sweeney and Roper 1998. Tbere are a number of deep-ses genera that are poorly studied or not studied ...................................................... 25 .Chapter2 Figures: Fig. 1. Location of adult octopuses collecteci fkom the Bay of Fundy in the summerofl995 ................................................ 38 Fig. 2. The changes in wet weight of hatchling octopuses over the. The fitted exponentiai growth equations are: live volutator: PO. 199e0-0M7' (M.75, p=O.OOOl), live Gammarus spp.: y=0.207e0-m3<"(M.34, FO.000 1), Sozen Gmmmspp.: y+. 194e4-M'"(&l.~~,p=û.69), Ophiopholis sp. :y0.1 97e4-W24t (*. 11, p=0.004), fiozen haddock: y=0.202e4.MaSt(W. 15, p=O.OO1).Where y is octopus weight m grams and t is tbe m days. Octopuses only ghed weight when fèd livefood ...................................................... 46 Fig. 3. Percent &al for octopuses in the fÏve treatments. Survival of octopuses was highest in the two hefood treatments ................... 50 Tables: Table 1. Prey species. This was determhed nom the % of Bat?zypolpus arcticus which contained tbat type of prey in their stomachs (modified fiom O'Dor and Macalaster 1983) ..................................... 36 Table 2. Corry,arjsons of the instantanmus relative growth rates (G) and physiologïcal instantaneous growth rate for some cephalopods ............ 49 Table 3. Nutritional content and energy per gram for the four food items used ....... 53 Table 4. Cornparison of the Gross Growth Efficiency (GGE) and food intake for severaIspeciesofoctopus ....................................... 60 Chapter 3 Figures: Fig. 1. Simplined diagram of the flow-through system and room set-up used in this expriment. Anhient water was used instead of chilled water in the winter when the ambient temperature was low ......................... 69 Fig. 2. Distriiution of Bathypolp arcticus along the east coast of North America, Data nom Macalaster (1976) ............................... 7 1 Fig. 3. Average sizes of octopuses in the four experimental treatments. Octopuses kept at 10°C grew much Merthan those at Iower naturd temperatures ...... 79 Fig. 4. Conservative estimates of age at maturity for B. arcticus at 4 Merent temperatUres. The longest lived octopuses in the 6°C and 10°C treatment are shown for cornparison along with the entire Hie span of the Florida Pygmy Octopus (Ocropus sp. 'Bubinf'). This mode1 predicts that on average, B. arcticus living at their naturai temperatures of 4°C take at least 6 years to reach maturity ................................. Tables: Table 1. Average weights (in grams), standard deviation and -le size for octopuses in each of the temperature treatments ....................... 75 Table 2. Growth rates (G) and physiological growth rates (G/T)of various species of hatchling octopuses. See the slopes on Table 3 for the gro wth rates fkom the regression equations Even when temperature is corrected for by ushg degree-days, B. arcticus grow very slowly compared with octopuses