whales

From: Mike Williamson (williams@whale.wheelock.edu)
Date: Sat Nov 15 2003 - 09:52:03 EST

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    Subject: Research paper

    Kenly,

    All are good questions. Looks like you have done a good job picking them. Here goes???

    1. The differences between dolphins and porpoises ??? Biologically, porpoises are small second cousins to dolphins. There are several physical differences, but the main one is that porpoises have teeth that are flattened on the sides and rounded (sort of like the ???spades??? in a deck of cards). Dolphins have teeth that are cone shaped. There are also differences in social behavior as well. Now here is the confusing part ??? some types of dolphins (bottlenosed dolphins mainly) are commonly called porpoises. This is just a common name, that is sort of like a nick name. So while you can sometimes get away with calling some dolphins porpoises, scientifically speaking you can never get away with calling a true porpoise a dolphin. If that is not confusing enough for you, there is a type of fish (also called a ???mahi???mahi???, or Dorado) that is called a ???dolphin???. So if you are ever in a restaurant and see ???dolphin??? on the menu don???t flip out ??? it is the fish they are frying .

    2. Some environmental hazards that could be prevented ??? One would think that the ones caused by people would be the ones that would be the most preventable. Turns out that this is easier said than done and many things that are hazards to whales and dolphins have benefits somewhere else, and making the trade offs is not always easy. Some are relatively straight forward. For example inexpensive modifications to fishing gear that prevents the capture of porpoises (small noisemakers called ???pingers???) seem to be cheap, and effective and do not appear to cause problems with the gear or effect the catch. Unfortunately, not all hazards are so easily managed.

    3. What do I think of the whaling issues? OK ??? first some background ??? I grew up in New Bedford, MA. , the city that once was the whaling capital of the US (about 150 years ago). Whaling was a part of the local history there, and it was probably the most affluent time that area ever knew.

    Anyway, as I see it there are really two whaling issues. One issue is whether it is OK from a biological standpoint to hunt whales. Basically will we damage populations and the environment by hunting them? These days, there are populations of some whales(grey whales, minke whales) that are large enough to think that they could be hunted and that (properly managed) the hunting would do no harm (there are some that would argue that hunting might do some good). The trick would be to have enough information and the ability to manage a hunt properly. In fact population management and hunting goes on in other wildlife (deer for instance) and it seems to work. So I see this as a management problem.

    The second part is whether it is ???right??? (or ethical) to hunt whales at all. This is a moral question and probably has a lot to do with how you were raised. Some cultures eat animals that we in the US keep as pets. I have a hard time thinking that my values are the best ones for everybody so I generally accept that some folks will feel that it is OK to hunt whales (even if I do not).

    4. Are dolphin safe nets and practices saving dolphins? As with most of these problems yes and no. The dolphin safe nets, and techniques themselves definitely have resulted in the boats using them catching fewer animals. The catch (no pun intended) is that not all boats use the techniques or nets. As a result animals still get caught, and generally by boats from countries that are paying less attention to how many animals are caught. So good news/bad news.

    5. As far as fishing goes, porpoises (which tend to be coastal animals) tend to be caught in nets used in coastal fisheries. In the part of the country I live in (in the Gulf of Maine), this would be ???gill nets???. These are large nets that are hung close to the bottom to catch bottom fish that run into the net. The problem is that the porpoises seem unable to avoid the nets as well. This has been improved by adding noisemakers (small devices called ???pingers???) to the nets that allow the porpoises to ???hear??? the nets. And there has been a lot of effort by managers and the folks fishing to try to set nets in places (and at times) when there are no porpoises in the area. This has helped (at least around here).

    6. Well there is hope. The last new species of whale was named only about ten years ago, and most folks are fairly certain that there are species that have not been found yet. There are presently some sub-species that are still being argued over and have not been named at all yet (see http://www.crru.org.uk/education/factfiles/taxonomy.htm). Anyway, it means being the one to discover the species so keep at it and who knows ???. Phocoena kenly ??? has a nice ring to it ???

    ge

    -----Original Message-----
    From: IceDragon4Ever@aol.com
    Sent: Oct 14, 2003 11:39 PM
    To: gearly1@earthlink.net
    Subject: Re: Research paper

    <HTML><FONT FACE=arial,helvetica><FONT COLOR="#000080" SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0"><B>Mr Early,<BR>
           Thanx sooo much!! Ok my 6 best questions.....well I've been thinking about it and here is what I 've been able to come up with. My report is on Marine Mammals and I had to choose 3 catagories....Whales, Dolphins, and Porpoises. So here goes!<BR>
    <BR>
    1. What are the differences between dolphins and porpoises?<BR>
    2. What are some environmental hazards to these creatures that could be prevented?<BR>
    3. What are your beliefs on the whaling issue?<BR>
    4. Are Dolphins-safe tuna nets actually saving dolphins?<BR>
    5. A big threat to whales is whaling and to dolphins it's tuna nets, are there <BR>
           any threats like that for porpoises? if so, what?<BR>
    6. Are there any species that we know of that have not yet been named?<BR>
    <BR>
    Thanks again sooo much! I'm sooo glad you wrote back and are willing to help...I wrote seaworld too and all they wanted to give me was info. on seaworld. This will be a great help! I really appreciate this! Thanks again!<BR>
                                                                           -Kenly<BR>
    p.s. I sort of threw in #6 for the report and also for my own info. I want to discover a species and have it named after me or get to name it! Thanks again!</b></font></html>



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