I currently live on the southern coast of Texas, not too far from Corpus Christi. Texas (27% bigger than France) has 1631 miles (2624 km) of Atlantic Ocean coastline along the Gulf of Mexico. It's relatively warm most of the year compared to many other places, and our latitude near Corpus Christi is roughly the same as southern Algeria and New Delhi, India. The coastline of Texas is mostly shallow wetlands, bayou, and inland bays sheltered by barrier islands. Much of the remaining real wilderness in Texas is the massive coastal estuary.
In Texas we are lacking in grizzly bears but in the coastal estuary we have lots of alligators and some pretty big feral hogs. Living on the water I also keep an eye on the presence of sharks.
How big?
Wild hogs are all over Texas and it's open season on them 24/7/365. The largest wild boar killed by a hunter in Texas and weighed was 790 pounds. However, I saw one that I bet weighed in as big or bigger that was hit and killed by a truck on highway 77 south of Victoria. From a distance I initially thought it was a dead cow.
As for sharks, not too long ago someone caught a 13 foot long tiger shark near Port Aransas, my home turf. The largest bull shark caught locally was about 500 pounds. A lot of the shark attacks in the USA are from bull sharks. They are aggressive and they are fresh water tolerant, known to swim up rivers.
Very recently they captured live the largest alligator ever found in Texas that was weighed and measured. It was 13 feet 8 inches long and it weighed in at over 900 pounds. Ones that are almost as big are not that rare. A while back someone killed and harvested a very large alligator in Mississippi that was 910 pounds and was believed to 185 years old. It still had several bullets in it's hide that are believed to be from the Enfield Pattern 1853 rifle-musket, a common weapon with Confederate troops during the Civil War. The largest alligator on record to be harvested in the USA was killed recently in Alabama and weighed in at 1011 pounds.
The largest I've seen killed locally was shot by a friend of mine in his backyard. It measured out at a bit over 9 feet long, but it wasn't weighed before they butchered it for the meat and the hide. Alligator tastes and is textured like chicken but with a hint of catfish flavor.
Professional alligator hunters will typically use a .22LR, a .17HMR, or a .22mag to avoid damage to the hide. When they shoot them they commonly have the alligator on a large hook baited with gator caviar (spoiled raw chicken). This one, found by surprise in their backyard, they were taking no chances with. They shot it with a 12 gauge Remington 870 with a fully rifled barrel using a .50 caliber sabot round (a common deer load in the eastern US). During alligator hunting season, non-commercial hunters will typically drive a large stake into the ground not far from the water and impale a raw chicken on it (preferably spoiled), then wait for an alligator to show up.
An alligator's jaws are weak on opening but it can bite down with roughly 3 times the force of a lion. Even a 5ft alligator that you stumble upon by surprise looks like an escapee from Jurassic Park.
Alligator's are surprisingly fast and agile on level ground, with the smaller ones being faster and more agile on land. A smaller, 4 to 5 foot long alligator can sprint at up to 25 mph (40 km/hr) which many dogs have found out to their demise. What a lot of people don't know is that an alligator can climb a chain link fence. Below is a video of one doing that.
[video=youtube;7Qp_bUYPrTg]https://www.youtube.com/watch?v=7Qp_bUYPrTg[/video]