Where
did we go?
We boarded the Robert E. Brownlee, the research vessel of the Marine
Science Institute, and ventured ou to the middle of the San Francisco
Bay. |
It
took all of our strength to haul in the net the boat was towing.
|
What
did we do?
The Robert E Brownlee is a 70-foot research vessel that was specially
designed to help people learn about San Francisco Bay. We used nets
to catch fish and plankton and learned to identify them. We viewed
the live plankton through a microscope. |
Torri and Melissa look closely for marine life in the big tank. |
|
Boat
Trip to San Francisco Bay
It was an excellent trip. We dragged a net behind the boat
and pulled it out of the water with a long line. We saw a
lot of animals when we took the net out of the water. Some
animals we took out of the water were:
Bat
Rays
Leopard Sharks
Shrimp
Starfish
We
did other things like learn the different parts of the boat,
such as the bow, stern, starboard, and port.
Tasia Beach
|
|
| One
of the most exciting parts of the day was seeing and touching baby
leopard sharks and sting rays that we caught in nets. We were surprised
to learn that the skin on the sharks and rays was rough like sandpaper. |
|
|
In
the chart above, note the changing shorelines of San Francisco
Bay between 1850 and today. San Francisco Bay is much smaller
and shallower today.
|
Not
So Cool Science Facts!
Believe
it or not, the average depth of the San Francisco Bay is only 12
feet. Captain Jackson, the skipper of the Robert E Brownlee, told
us that in 1850 the average depth of the Bay was 43 feet. That’s
right. Over the last 150 years the bottom of the bay has risen 31
feet! Where did all this sediment come from?
Most
of the mud in the San Francisco Bay came from the Sierra Nevada
mountains. During the Gold Rush, mining companies destroyed many
mountainsides in their quest to find gold. They used high-pressure
water to blast away huge mountains. Over the years all the sediment
loosened by hydraulic mining has gradually washed into the Sacramento
River. This led to the deposition of tons of sediment in the San
Francisco Bay.
|
