Sounds, Seas, and the Singing Fish: The Impact of Underwater Noise Pollution and the Importance of Habitat in Laboratory Studies

Sounds,

S e a s,

and the

Singing fish:

Eva MacLennan

Department of Biology March 8, 2017 This research was supported by the Jamie Cassels Undergraduate Research Awards,

University of Victoria Supervised by Dr. Francis Juanes & Kieran Cox, Department of Biology

Porichthys notatus

Also known as the plainfin midshipman, or the singing fish

• Males ‘sing’ to attract mates

• Due to the importance of sound to

their reproductive success,

P. notatus

is a model organism for soundscape

research

Structural complexity affects behaviour

Habitat should always be taken into account during behavioural studies in the laboratory.

Habitat affects fish behaviour, but at this point in our analysis, boat noise has not emerged as a significant variable

Responses to boat noise varied in direction, but appear to be of lesser magnitude in more complex habitats

Sound does have an effect on fish

It has been well-documented that sound impacts fish behaviour, but this is not clear in our results; it is possible that this response

was overshadowed by the effect of habitat.

• Fish behaved more similarly between the two

sound treatments when they were in more

complex habitats, relative to the empty tank

Shipping - fishing - seismic exploration - sonar

The soundscape is an important source of

information in the marine environment

Fish can sense sound through their ears and their lateral

line.

• Fish spent less time resting and more

time being active when they were in an

empty tank

• Fish spent more time in the water

column when in an empty tank

empty tank

+ pebbles

+ brick shelter

We assessed fish behaviour with and without exposure to boat noise – and in each of three habitats:

1. How does boat noise impact the behaviour of

P. notatus

, a fish that uses sound to

communicate?

2. Can habitat complexity moderate this

behavioural response?

Will fish act more similarly between sound treatments

(presence and absence of boat noise) if they have a

more complex habitat to interact with?

more

scatter

less

scatter

References

1. Andrew, R. K., Howe, B. M. & Mercer, J. A. Long-time trends in ship traffic noise for four sites off the North American West Coast. J. Acoust. Soc. Am. 129, 642–651 (2011). 2. Širović, A., Varga, L. M. & Oleson, E. M. Long-term trends in ambient and anthropogenic noise in central and western Pacific Ocean. 27, 40001 (2016).

3. Vasconcelos, R. O., Amorim, M. C. P. & Ladich, F. Effects of ship noise on the detectability of communication signals in the Lusitanian toadfish. J. Exp. Biol. 210, 2104–2112 (2007). 4. Simpson, S. D., Purser, J. & Radford, A. N. Anthropogenic noise compromises antipredator behaviour in European eels. Glob. Chang. Biol. 21, 586–593 (2015).

5. Wysocki, L. E., Dittami, J. P. & Ladich, F. Ship noise and cortisol secretion in European freshwater fishes. Biol. Conserv. 128, 501–508 (2006).

Acknowledgements

This project would not have been possible without the hydrophone data supplied by Ocean Networks Canada, the beautiful

P. notatus

supplied by the Balshine Lab of McMaster University, the bioacoustics tutelage of Dr. Erica Staaterman, the moral support of the Juanes

and Baum Labs of the University of Victoria, and the hard work and dedication of my incredible volunteers: Sarah Brittain, Bryttni

Nameth, and Nick Patterson.

My hugest thanks to everyone involved!

Anthropogenic noise inputs in the oceans are

increasing

1,2

This has the potential to continue to impact marine species:

• masking biologically important sounds, including

vocalizations

3

• affecting predator-prey relationships

4

• inducing stress, leading to reduced fitness and

reproduction

5