Pristis+pristis


=Pristis Pristis = =(Common Sawfish) =

=CLASSIFICATION: = = = 
 * Scientific Name: Pristis Pristis
 * Species Authority: Linnaeus, 1758
 * Regular Name: Common Sawfish
 * Kingdom: Animalia
 * Phylum: Chordata
 * Class: Chondrichthyes
 * Genus: Pristis
 * Order: Pristiformes [[image:http://news.bbc.co.uk/media/images/40626000/jpg/_40626389_rev_sawfish.jpg width="270" height="270" align="right" caption="http://news.bbc.co.uk/media/images/40626000/jpg/_40626389_rev_sawfish.jpg"]]
 * Family: Pristidae

=INFORMATION: =

**Location of Ecosystem**

 * They live in muddy and shallow waters
 * can be found in estuaries and shallow bays
 * can be in freshwater and saltwater
 * prefer freshwater such as river mouths
 * specific location: Atlantic Ocean (northeast, southeast, and eastern central)
 * latitude ranges: 0° 60° N - 6° W 0°

**Physical Habitat features**
TEMPERATURE: SALINITY: TIDES: TIDAL RANGES: GEOLOGICAL PROCESSES: 
 * 10-25 degrees C
 * 36-37 ppt
 * Labrador Current
 * Gulf Stream
 * North Equatorial Current
 * South Equatorial Current [[image:http://www.flmnh.ufl.edu/fish/education/questions/sawfish1.jpg width="300" height="196" align="right" caption="http://www.flmnh.ufl.edu/fish/education/questions/sawfish1.jpg"]]
 * North Brazil Current
 * Guinea Current
 * Angola Current
 * Brazil Current
 * Benguela Current
 * South Atlantic Current
 * high: 4.88
 * low: 0.02
 * Submarine ridge extending north and south ridges (1-3 km) above ocean bottom
 * Along coasts- continental shelves and mid atlantic ridge divide eastern and western floor into basins (abyssal plains)
 * Basins: North American, Brazil, and Argentina
 * Trench in Puerto Rico; 8742 m below surface
 * does not have many active volcanoes

Characteristics of Habitats
ESTUARIES LAGOONS
 * have an opening connecting to the ocean.
 * affected by tides, waves, and salinity (oceans)
 * has sediment and flowing freshwater
 * made up of salty fresh water[[image:http://www.sms.si.edu/irLspec/images/LagoonXS.jpg width="397" height="157" align="right" caption="http://www.sms.si.edu/irLspec/Whatsa_lagoon.htm"]]
 * average salinity is 35-37 psu
 * are separated from the ocean/sea
 * usually separated by barrier islands
 * have tidal waves, channels, and interaction with ocean water
 * are usually shallow

**Migration Patterns**

 * migrate between saltwaters and freshwaters
 * migrate for food and/or due to climatic changes

**Population**

 * 1975: 60,000-100,000 sawfish caught a year
 * 1980s: caught almost 1,000 sawfish a week
 * 1998: about 4-6 sawfish are accidentally caught

Anatomy
<span style="font-family: 'Times New Roman',Times,serif;"> <span style="font-family: Arial,Helvetica,sans-serif;">
 * <span style="font-family: Arial,Helvetica,sans-serif;">sawfish take in water through the spiracles [[image:http://www.flmnh.ufl.edu/fish/sharks/sawfish/sawfishanatomy_external.jpg width="349" height="161" align="right" caption="http://www.flmnh.ufl.edu/fish/sharks/sawfish/sawfishanatomy_external.jpg"]]
 * <span style="font-family: Arial,Helvetica,sans-serif;">spiracles are located above the eyes
 * <span style="font-family: Arial,Helvetica,sans-serif;">have no bones in their bodies
 * <span style="font-family: Arial,Helvetica,sans-serif;">have a cartilaginous skeleton
 * <span style="font-family: Arial,Helvetica,sans-serif;">males have intromittent organs called claspers
 * <span style="font-family: Arial,Helvetica,sans-serif;">females have no claspers
 * <span style="font-family: Arial,Helvetica,sans-serif;">claspers are located in the pelvic fins
 * <span style="font-family: Arial,Helvetica,sans-serif;">have pectoral fins located by the head
 * <span style="font-family: Arial,Helvetica,sans-serif;">scales on a sawfish grows in number not in size
 * <span style="font-family: Arial,Helvetica,sans-serif;"> The rostrum (saw) is made of cartilage
 * Pectoral fins have little fat and muscle in them

<span style="font-family: Georgia,serif;">**Reproduction**

 * Breed live birth
 * babies are born in weak egg shell and get nourishment off egg sac
 * baby sawfish aka pup are born with blade
 * blade is covered in a rubber substance to protect others
 * rubbery cover eventually breaks downs and falls off
 * they mate every two years
 * each mother has an average of 8 pups
 * babies mature slowly, takes 10-12 years (parental care)[[image:http://www.itsnature.org/Sea/images/article-images/Sawfish-1.jpg width="350" height="223" align="right" caption="http://www.itsnature.org/Sea/images/article-images/Sawfish-1.jpg"]]
 * reproduce at lower rates than most other species of fish
 * live for about 25 - 30 years
 * gestation period lasts about 5 months

<span style="font-family: Georgia,serif;"> **<span style="font-family: Georgia,serif;">Appearance **

 * body is flat
 * Head is flat
 * has a long, flat, blade nose
 * 16 - 20 teeth surround the blade
 * have 80 - 160 teeth in their mouth (upper/lower jaw)
 * teeth are long and slightly rounded
 * nose can be 1/5 of total body length
 * skin is black/gray on top and sides
 * skin is creamy white on belly side
 * have gills on the bottom rather than sides
 * can get up to 5 meters in length
 * skin has rough texture due to little teeth-like scales

<span style="font-family: Georgia,serif;">**Food Chain; Food Web**

 * adult sawfish are on the top of the food chain
 * they can been eaten by animals such as sharks, crocodiles, and even dolphins (though that's rare)
 * they eat small fish and marine animals that can be digested whole because they do not have teeth to tear apart animals.

==<span style="font-family: Georgia,serif;">**Economical Importance** ==
 * saws are used as souvenirs
 * fin of sawfish is a delicacy in some places
 * dried fin is sent to shark fin market for sale
 * sawfish meat is edible

<span style="font-family: Georgia,serif;">**Physical Habitat**

 * lives in estuaries and lagoon
 * lives in freshwater habitats
 * lives in coastal areas

[[image:http://www.flmnh.ufl.edu/fish/gallery/descript/KTSawfish/pancas.JPG width="200" height="144" align="right" caption="http://www.flmnh.ufl.edu "]]

 * the population of common sawfish is still decreasing (according to the IUCN Red List)

<span style="font-family: Georgia,serif;">Reason of Extinction

 * overfishing for fins ( delicacy in places)
 * overfishing for sawlike nose ( souvenirs)
 * bycatch ( and not release animals carefully)
 * year of extinct: 2003

<span style="font-family: Georgia,serif;">**Protection of Sawfish**
 * Sawfish are an endangered species and are therefore protected. The sawfish is illegal to fish for. If one is caught, it has to be released quickly and carefully back into the water. The sawfish is on the IUCN Red List of Threatened Species.

<span style="font-family: Georgia,serif;">Possible Solutions:

 * Detach sawfish extremely carefully to avoid harming/killing the sawfish
 * When releasing sawfish from nets and such, try to keep body (atleast the gills) in the water for all long as possible.
 * Reduce amounts of fishing for sawfish.
 * Have restrictions on fishing in habitats that are heavily influenced by sawfish.
 * Educate people on the harmful effects that overfishing of sawfish can have on the marine ecosystem and possibly in the future other biomes.
 * Report catchings of sawfish.



<span style="font-family: Georgia,serif;">QUESTIONS: 1. What are two possible solutions for common sawfish? 2. Name a predator and a prey of the common sawfish. 3. What are some physical features of a common sawfish?

<span style="font-family: Georgia,serif;">Sources

 * http://www.mote.org/index.php?src=gendocs&link=Sawfish-How%20you%20can%20help&category=Shark%20Research
 * http://irregulartimes.com/index.php/archives/2008/02/27/save-the-sawfish/
 * http://www.arkive.org/common-sawfish/pristis-pristis/description.html
 * http://www.absoluteastronomy.com/topics/Sawfish
 * http://www.com.univ-mrs.fr/IRD/atollpol/fnatoll/uktse.htm
 * http://www.sms.si.edu/irLspec/Whatsa_lagoon.htm
 * http://www.flmnh.ufl.edu/fish/sharks/sawfish/sawfishanatomy.html