Under construction This article is under vigorous construction. Content will change quickly.

Big Brook is a fossil site in Monmouth County, New Jersey.

The FormationEdit

Most of Big Brook's fossils are from the Late Cretaceous, around 75 mya. At that time the area was covered in water, so many fossils of marine life are found there.

Some parts of the brook are of Pleistocene age, so fossils from animals such as mastodons can be found in these areas.


Fossils are collected straight in the brook, so some special supplies are required.

  • Screening box: Basically, a frame with a screen attached to it, allowing you to strain for fossils. You can build your own, or just grab a large household strainer.
  • Trowel: You'll need a trowel to scoop gravel into the screening box. Any regular garden trowel will do.
  • Milk crate: You'll also need something to sit on if you're collecting in the brook, unless you want a wet bottom. Milk crates work best (as you can carry all your supplies in it later), but any sturdy box will do. Stools should probably not be used, as the river bottom is uneven.
  • Specimen containers: Something to hold your finds should be brought. As most Big Brook fossils are small, film jars, plastic containers, and Ziploc bags work well. Glass containers shouldn't be used, they break easily.
  • Clothing: Certain types of clothing are best for the area. It all gets soaked eventually, but jeans are best for avoiding thorns or other obstacles. Jeans also dry out quickly, which is much relief for the wet collector. Bare feet or sandals aren't a good idea, there can be unpleasant shards of glass in the stream. Old sneakers or boots are best, or hip waders if you can find some for a reasonable price. As summer is the best time to collect, the final piece of attire is the hat---it keeps you from getting sunburned and looks good on all paleontologists.
  • Other: Dry socks and shoes will be beneficial on the ride home, as well as towels to dry off. The height of fossil collecting season is also the height of bug season. Bring insect repellent to ward off mosquitos and ticks. If you expect to be collecting the whole day, a pack with lunch and snacks can be of use, as long as it stays out of the water.
  • Common sense: Safety is crucial. There are some bits of glass in the stream, so watch where you put your feet and fingers. Bring some Band-Aids and Neosporin just in case. You have to park on the road to get to the brook, so watch for other cars. Unless you have to answer the call of nature and go somewhere away from the brook, stay out of the woods, as the banks can be unstable and ticks are prevelant. And if it starts raining, leave---the river rises quite quickly and you can be underwater before you know it.

Some areas on the side of the brook are private property, so please do not walk into these areas (they are posted as such).


Shark teeth are very common here, and perhaps they are what Big Brook is most famous for, but many other fossils have been found here.

Cartilaginous Fish (sharks, rays, etc.)Edit

If you find only one type of fossil at Big Brook, these will most likely be it.

Scapanorynchus texanus

Scapanorynchus is a type of goblin shark. It grew to around 3 to 5 meters long. They are often longer than teeth of other shark species. Many times the tooth tips are worn off and can be mistaken for other shark teeth.

Rarity: Very common. Scapanorynchus's teeth are the most common vertebrate fossil at Big Brook.

Squalicorax pristodontus

This is one of the two Squalicorax species, the crow sharks, at the brook. S. pristodontus likely grew to around 3 meters or so. The genus's teeth are very distinctive, being short and wide.

Rarity: Very common.

Squalicorax kaupi

The second of the crow shark species. They are similar to S. pristodontus except smaller.

Rarity: Very common.

Bony FishEdit

Bony fish fossils can be found when you look for them.

Enchodus petrosus

Enchodus petrosus is a primitive, saber-toothed salmon. It grew to around 1 to 2 meters long. Two other Enchodus species occur here: E. gladiolus and E. ferox.

Rarity: E. petrosus is a very common fish in Big Brook and the East Coast in general. Its teeth are very common and jaw fragments common. E. gladiolus is less common, and E. ferox is rare.

Anomaeodus phasolus

Anomaeodus phasolus is a pycnodont fish. Judging by the known finds, it grew to around 0.5 to 1 meter. Teeth are usually the fossils found.

Rarity: Teeth are less common, while vertebrae are uncommon.

Xiphactinus audax

Cross a bulldog with a fish and you get Xiphactinus. Dagger-like teeth are very occasionally found here. It grew to around 4 meters or so.

Rarity: Very uncommon.


A few reptile fossils are found at Big Brook.

Mosasaurus conodon

The majority of mosasaur material from Big Brook comes from this species. Its adult size is estimated to be about 3 to 6 meters. Teeth, vertebrae, and jaw fragments are the material recovered so far.

Rarity: Less common, but the most common of the Big Brook mosasaurs.

Mosasaurus maximus

The largest of the mosasaurs, growing to a whopping 13 meters. Sometimes teeth and jaw fragments of this species are recovered.

Rarity: All M. maximus material is rare.

Proghathodon rapax

Another genus of mosasaur. Their teeth are similar to M. conodon's except they are smaller and shorter. Like M. conodon, they grew to around 3 to 6 meters.

Rarity: Very uncommon.


Very few dinosaurs are found in Big Brook. If dinosaur material is found, it is best to call the New Jersey State Museum for assistance, who may even let you dig the bones out with them.


Some hadrosauroid bones have been found here, mostly skull fragments and leg bone fragments. Probable candidates for identity are Hadrosaurus and Edmontosaurus.

Rarity: Very uncommon.

Dryptosaurus aqualunguis

Dryptosaurus is a relative of Tyrannosaurus, unique to the state! It grew to 6 meters or more. Toe bones, teeth, and claws have been found.

Rarity: The rarest of the rare.

Other dinosaurs

Some dinosaur material from the brook has been assigned to genuses such as Ornithomimus (sometimes Coelosaurus) and Nodosaurus. Only one or two scrappy fragments have been found, so these will not be covered.


Sometimes you can find mammal bones in the brook, both ancient and modern.

Mammut americanum

Mastodon bones are occasionally found here. Vertebrae and teeth are represented.

Rarity: Vertebrae are very uncommon, teeth are rare.

Odocoileus virginanus

This is just the scientific name for the modern white-tailed deer. Antlers have occasionally been recovered.

Rarity: Uncommon.

Rangifer tarandus

This is a caribou (reindeer). Antlers date to the Pleistocene epoch.

Rarity: Rare.


Aside from shark teeth, these are the most common fossils found in Big Brook.

Exogyra costata

This is an oyster. Fragments or whole shells are frequently found here.

Rarity: Very common.

Pycnodonte convexa

Another oyster, which is sometimes confused with Exogyra. On both oyster fossils, the remains of boring sponges can be commonly found on the shells, making for an interesting display.

Rarity: Very common.

Agerostera mesenterica

This is another oyster of two species, A. mesenterica and A. falcata. It has a "U" shape.

Rarity: Very common.


Very occasionally, artifacts from humans can be found in the brook. While not strictly fossils, these finds are often unexpected and can be a great surprise to find.


Archaic arrowheads are found, but not very often.

Rarity: Uncommon.


Bottles from colonial times have been found in the brook.

Rarity: Uncommon.


Once, a vintage penny has been found in the brook, dated 1826. Only one has been found, and it is unlikely more will ever be uncovered---but it is an interesting find, so just be aware of the possibility.


No actual plant fossils are found in the brook, but rarely pieces of cedar bark are uncovered. These aren't very old and are probably quite recent.


There are ironstone concretions in the brook that look like several types of fossils such as crocodile teeth, dinosaur toe bones, and others, so watch out for them, as they can get annoying. Usually if you are uncertain whether or not an object is a concretion, it is usually best to take it to an expert for identification.