DOC PREVIEW
UNCW BIO 358 - Out of Class Lecture Notes

This preview shows page 1 out of 4 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 4 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 4 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

BIO358-001 1st Edition Lecture 19Outline of Last Lecture I. Methods of Tracking divesII. D-TagIII. Right Whale D-Tag StudyIV. Beaked Whale D-Tag Study Outline of Current Lecture I. Answers to questions Current Lecture(1) What are some of the anthropogenic sources of sound in the ocean?- shipping- commercial recreational – fishing - high resolution imaging- explosives- air guns (2) Is noise in the ocean increasing? If so, by how much, and why?-increase in 3Db per decibel in certain parts – northern hemisphere – due to shipping (3) Which frequency of sounds (low or high) travels farther in the ocean? What is a good marinemammal example of a long-range acoustic signal travel through the ocean?- Low frequency travels much better than high frequency (ships make low frequency)- Subwoofer sound goes through the whole room- Higher frequencies need to be pointed right at you to hear it. These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Low frequency sounds can travel VERY far in the ocean (3) True/False. Seismic airguns and sonar are high-amplitude sounds. - True (4) What is the largest source of anthropogenic sounds in the ocean?- Shipping - Seismic is getting there (5) A concern about increasing levels of shipping noise is “acoustic masking”. What does this term mean?- It is getting too loud for communication - Animals unable to use communication space when ships go by (6) Is there any evidence that exposure to chronic noise causes physiological changes in anyorganism?- Rats – exposed chronically to noise throughout life – adrenals higher in mass than expected, other organs, less heavy than expected. Smaller young, young that do not thrive as well. - Heart rate and behavior from resting to non-resting with exposure to noise - Stress – increase in adrenals and thyroid – measure steroid levels in fecal samples of whales. Trained dogs to smell whale poop… -(7) Please be able to discuss the study that was able to infer that shipping noise might impact right whale stress levels (Rolland et al.2012).- Frequency in Hz - Shipping after 9/11 shipping turned off for a few days – reduction of noise –- Fecal glucocorticoid metabolites before and after 9/11 – drop from before and after 9/11– substantial drop in glucocorticoid metabolites in whale fecal samples (9) What is the largest source of noise from large ships?- The propeller cutting through the water - “propeller cavitation” makes hole in the water and the water caves in to that hole making noise. -(10) Is the IMO (International Maritime Organization) taking steps to reduce ship noise? Please also know that the European Union has proposed that shipping noise (and other anthropogenic sources) be identified as a “marine pollutant”.- Engineering project – to reduce ship noise- Long term solution, ships last 3 decades(11) True/False. Marine shipping is expected to decrease by 50% by 2030. - False (12) In a general sense, how do seismic air guns work?- Large boat tows an array of air guns (used to use dynamite) - Massive air compressors that send air to gun- Highly compressed air hits water and expands and then contracts and makes a controlled explosion - Signal every 12-10 seconds - Hydrophones to hear the return sound and how it changes - Data produced – shows if there is gas/hydrocarbon on the seafloor (13) Do seismic air gun pulses travel far in the ocean? If so, what magnitude of distance can theytravel?- Yes- Kilometers- Long distances - 3900 km (14) Is there any evidence that any marine mammal might change any aspect of its behavior in the presence of seismic air gun activity?- Fin whales – before survey – number of calls higher than after the survey and they moved from where they wanted to be. - Sperm whales – change in foraging rate – massive reduction in “buzz” rate which indicates feeding – reduced feeding, as you move closer to the air gun array. (15) Oil and gas seismic exploration in the mid-Atlantic – think about what some of the potentialimpacts are on marine mammals. Is there the potential problem of cumulative effects?- Chronic stress – smaller calf sizes?- Difficulty communicating for mating and feeding- Disruption of migration pathways - Disruption of body weight due to disruption of feeding - Cumulative effects –not much research done – more


View Full Document
Download Out of Class Lecture Notes
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Out of Class Lecture Notes and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Out of Class Lecture Notes 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?