Subject: Killer whales

Al Romero (romero@macalester.edu)
Mon, 08 Feb 1999 13:35:20 -0600

At 08:03 PM 2/6/99 -0500, you wrote:
>Dear Aldemaro,
>	My name is Jennifer HUckaby, and I am doing a report on killer whales.  I
was
>hoping that you could give me some information.  I have piles of questions.
>1.  what are some typical illnesses among orcas?

A number of internal parasites have been reported for Orcas (a preferred
that name that "killer" whales). Also, gum disease has been found in some
individuals.

>2.  do orcas ever have multiple births?

I am not aware of reports of multiple births among orcas; however, among
other species of whales and dolphins multiple births are rare and when they
happen, usually both (or at least one) of the calves die.

>3.  how old is too old to mate?

The average life span of an orca is 50 years for females and 30 for males.
There is no indication that there is an age "too old" to reproduce.

>4.  over the span of a lifetime, how many calves can a female produce?

Again there is no complete data to be sure of anything. Other species tend
to have 3-6 calves in their lifetime.

>5.  do they have only 1 mate all their life?

What we know (which is not much) suggests that they have multiple mates.

>6.  what is the oldest known orca?

Until recently it was believed that may be 40 years old; however more
recent studies indicate a maximum of up to 80-90 years.

>7.  how long can killer whales stay under water?

The longest recorded is 17 minutes but commonly they stay about 6 minutes
underwater.

>8.  can they swim faster under water or at the surface?

Most cetaceans swim faster under water. Speeds of up to 40 km/h have been
reported.

>	Any other information that you have would be very helpful.  I am a &th
grader
>at Mt. Tabor Middle School, so if you could put your response in text that I
>will understand , then that would be helpful, also.
>	Sincerely,
>	Jennifer Huckaby


Aldemaro Romero, Ph.D.
Director and Associate Professor
Environmental Studies Program
Macalester College
1600 Grand Ave.
St. Paul, MN 55105-1899
(651) 696-8157
(651) 696-6443 (fax)
romero@macalester.edu