Thesis defense

• 1. Masters Thesis Defense Shakira G. Quiones LebrnDo calves matter?: The effect of dolphinwatching on the acoustic behavior of apopulation of bottlenose dolphins in PanamThesisCommittee:Dr. Laura May Collado Dr. Alberto Sabat Dr. Mitch AideDr. David Logue

2. OVERVIEW Introduction to whale watching Chapter 1: Importance of calves when studying impacts of whale watching Chapter 2: Case study Acoustic behavior bottlenose dolphins of Bocas del Toro, Panam Conclusions Outreach Future work 3. WHALE AND DOLPHIN- WATCHINGHistory: From whaling to watching.IWC 1994 119 Countries WW generates $2.1 billion Recreational use =sustainable use 4. THE EFFECTS OF WHALE - WATCHINGShort-termLong-termconsequencesconsequences Boat strikes Increased death Disruption ofratesimportant behavior Abandonment of the Disruption of acoustic areacommunication.Bottlenose dolphins - Doubtful Bottlenose dolphins Shark BayPopulation Consequences of 2005) Sound, Acoustic(Bedjer NZ (Lusseau and Bejder 2007)Disturbances (PCAD) model 5. POPULATION CONSEQUENCES OF ACOUSTIC DISTURBANCES (PCAD) MODELWhat factors influence behaviorchanges? 6. CETACEAN SOUNDSCetaceans rely almost entirely on sound to communicate.Baleen whales: Low frequency modulated soundsSperm whales: Clicks (Codas)Other odontocetes: Higher frequency modulatedsounds and pulses 7. WHALE WATCHING AND NOISEThe noise produced by theengines overlaps with thecommunication signals ofmany marine mammalspecies.Masking Erbe 2002 Clark et al. 2009 8. RESPONSES TO BOAT APPROACHESBehavior responses Acoustic responses Behavior state Rate of communication Swimming synchrony signals Inter-breath interval Acoustic parameters of Direction and speed of communication signalsmovement 9. FACTORS INFLUENCING RESPONSES TO DISTURBANCE Experience Group size Received levels (RL) Group compositionof noise(mothers and calves). Distance and speed ofwatching vessel 10. CHAPTER 1:DO CALVES MATTER?:ADDRESSING THEIMPORTANCE OF INCLUDING CALFPRESENCE IN THE ASSESSMENT OF WHALE-WATCHING IMPACTS. 11. Introduction Calves are more susceptible to boat approaches. Having calves could affect mothers responses to whalewatching. Is it important to consider responses by groups withcalves? Method: Literature review 12. Table 1. Summary of published work on whale and dolphin watching showing the proportion of publications where calves areconsidered as a factor for changes in responses. Calves responded No difference inSpeciesCalves where not considereddifferently responseBehavioral responsesA. bottlenose dolphins (Tursiops Nowacek et al., 2001; ?Acevedo, 1991; Constantine, 2001,truncatus) Hastie, 2003; Lusseau2004; Buckstaff, 2004*; Lusseau, 2003*; Akiyama et al 2007 2004,2006; Mattson et al. 2005;Arcangeli et al. 2009, Mattson et al.2005; Janik, 1996)Indo-Pacific bottlenose dolphinsStensland and Berggren ? ?(Tursiops aduncus)2007; Hawkins and Gartside, 2010Pantropical spotted dolphins (StenellaMontero-Cordero 2007 ? ?attenuate)Sotalia costero (Sotalia guinensis)Santos et al. 2006 Filla et al. 2009?Common dolphin (Delphinus delphis)Stockin et al. 2008? ?Killer whale (Orcinus orca) Williams et al. 2002*? ?Irrawady dolphin (Orcaella brevirostris) ?Hashim & Jaaman 2011Chinese white dolphins (Sousa chinensis) ?Hashim & Jaaman 2011 13. RESULTS - BEHAVIOR STATESotalia guianensis Pantropical spottedBottlense dolphinsSantos et al. 2006 dolphins Stensland & Berggren Montero-Cordero 2007 2007Lemon et al. 2006 Less resting and feeding during interactions withArcangeli and Crosti boats for groups with calves. More traveling.Lusseau 2003 Lemon et al. only found changes from traveling to milling Lusseau found changes in female avoidance strategies 14. RESULTS - DIRECTION AND SPEED OF MOVEMENTBottlenose dolphins - Steckenreuter et al. Humpback whales- Stamation et al.2011 2009, Schaffar et al. 2008Killer whales - Williams et al. 2002 Gray whales?? 15. RESULTS - INTER-BREATH INTERVALSBottlenose dolphins - Nowacek et al. Humpback whales - Stamation et2001, Lusseau 2003 al. 2009Groups with calvesspend more timeunderwater: VerticalavoidanceSotalia guianensis - Filla & Monteiro 2009 16. RESULTS - SWIMMING SYNCHRONYNot enough evidence. Groups with calves are generallyless synchronized.Synchronization increases with the presence of boats. 17. RESULTS - ACOUSTIC RESPONSES Production of communication signals Groups with calves have a higher whistle production rate. For humpback dolphins, whistle rate increases when disturbed by boats, particularly when calves are present in the group. Lemon et al. 2006 found no reponse. Did not considered calves. 18. CONCLUSIONSDo calves matter? Yes. Average of response vs. targeting vulnerable groups. Better prediction of long-term consequences. 19. CHAPTER 2:DOLPHIN-WATCHING BOAT INFLUENCE DOLPHIN COMMUNICATION: THE EFFECT OF NUMBER OF BOATS ANDMODE OF APPROACH ON WHISTLE EMISSION RATE FOR GROUPS WITH CALVES 20. INTRODUCTION DOLPHIN COMMUNICATION SIGNALSWhistles are frequency modulated signals used forcommunication. 20Hz 32kHzEach individual has its own signature whistle used forgroup cohesion. Whistle rateoverall vocal behavior but can be used as a measure to noise impacts. Whistle rate = #whistles/#dolphins/time 21. Dolphins canpotentially increasetheir whistle repetitionto compensate for themasking noise.Separation betweenmothers and calveselicit a higher whistlerate. Buckstaff 2004 22. DOLPHIN WATCHING IN BOCAS DELTORO Small resident population of bottlenose dolphins (~100 dolphins) Daily interactions with dolphin-watching tour boat.FeedingSocial 23. PREVIOUS STUDIES IN BOCASChange in frequency andduration of whistles. (MayCollado & Wartzok 2008)Increase in call repetition.(Taubitz 2007)Ambient noise in Bocas del ToroMay Collado & Wartzok 2008Changes in behavior(Barragn-Barrera 2007)Calves? 24. Questions:Does dolphin-watching have an effect on whistlerate?Is it different for group with calves? 25. Challenges: Noise received levels (dB)? Too many boats at the same time Few dolphinsSolution:Use type of approach andnumber of boats as arelative measure ofacoustic disturbance. Signal:Noise (dB)Distance from observation boatBuckstaff 2004 26. MEASURING DISTURBANCE# Boats Type of Descriptionapproach Aggressive. Boats approaching dolphins at high N speeds, perpendicular to the O # 1 dolphins swimming B direction, and/or circling the I OA group. Closer than 10m.S T Close approaches (