Showing posts with label Delaware and Raritan Canal Trail. Show all posts
Showing posts with label Delaware and Raritan Canal Trail. Show all posts

Thursday, July 7, 2011

The Fight Against Invasive Species


The IUCN recently posted an article about "invasive aliens."  No, these are not the type found in summer movies like Super 8. These are the species - animal and plant - that invade habitats where they do not belong.

Biodiversity is being lost at an unprecedented rate, with a whole host of factors contributing to the disastrous declines. Habitat destruction is well-documented as being one of the leading causes of species extinctions, but invasive alien species are also to blame. But what exactly is an invasive species? Invasive species are those organisms which have been introduced by man, either accidentally or on purpose, to areas in which they are not naturally found, and have thrived to the extent that they have taken over their new environment.

It is important, however, to make the distinction between these species and ‘non-native’ species. Plenty of species are introduced to areas outside of their natural range, and are hence non-native, but not all of these will become invasive. Many will not be able to adapt to the new environment at all, and may eventually die off. Other non-native species cope well in their new surroundings without ousting native species from the ecosystem, co-existing without competition. An ecosystem can support this change as its original components and key players are still there. The non-native species may itself prove beneficial to human wellbeing and in some cases may become part of the landscape, as in the case of the Mediterranean Cypress (Cupressus sempervirens) in Tuscany or the Common Pheasant (Phasianus colchicus) in many areas of North America and Europe. What causes a species to be labelled as invasive rather than simply non-native is its ability to out-compete native species, impacting on the biological diversity of the region and even on the livelihoods of human communities.

Stink Bug  via http://media.nj.com/hunterdonnews_impact/

Invasive species in New Jersey include foreign bugs, plants, animals and aquatic creatures. Invasive species are introduced species that can thrive in areas beyond their natural range. They are characteristically very adaptable, aggressive, and have a high reproductive capacity. Their vigor combined with a lack of natural enemies often leads to outbreak populations that threaten and endanger native species.

For example, the East Asian stink bug is in NJ now and does literally stink.

The European green crab and the Asian Shore Crab threaten our native acquatic populations.

Flathead Catfish caught in the Delaware River near Lambertville
blogs.courierpostonline.com
The Flathead Catfish which is normally found in the Mississippi basin, has been found in NJ in places like the Delaware and Raritan Canal.


Giant Hogweed flower head
The Giant Hogweed sounds like something from science-fiction. This species that can grow up to 20 feet and it produces sap that cause blisters and severe burns that leave scars on humans.

Last fall, the first North American instance of invasive Chinese pond mussel was confirmed by New Jersey state biologists in Hunterdon County after DNA testing.

The USDA's website offers state lists and news. For NJ information, see invasivespeciesinfo.gov/unitedstates/nj.shtml

Further Reading

Friday, February 25, 2011

Delaware and Raritan Canal


Historic map of the D&R Canal
click image for large size via http://mapmaker.rutgers.edu
The Delaware and Raritan Canal (D&R Canal) is a canal in central New Jersey, that was built in the 1830s and served to connect the Delaware River to the Raritan River.

Delaware and Raritan Canal Company 24x36 Giclee
D&R Canal Company
It was intended as an efficient and reliable means of transportation of freight between Philadelphia, Pennsylvania and New York City, especially coal from the anthracite coal fields in eastern Pennsylvania. Before the advent of the railroads, the canal allowed shippers to cut many miles off the traditional route from the Pennsylvania coal fields. That route took the coal down the Delaware, into the Atlantic Ocean, around Cape May, and up along the coast to New York City.

Delaware and Raritan Canal at Work, The (NJ) (Images of America)The canal system was dug mostly by hand tools, mostly by Irish immigrants. Work began in 1830 and was completed in 1834, at an estimated cost of $2,830,000. When the canal first opened, teams of mules were used to tow canal boats through it (the steam engine was not yet applied to such uses).

The canal's greatest usage occurred during the 1860s and 1870s during the area's Industrial Revolution. On May 18, 1872, the D&R Canal Company was merged with several parallel railroads into the United New Jersey Railroad and Canal Company, and leased by the Pennsylvania Railroad. Over time, the importance of the D&R Canal waned as railroads were used to perform, more rapidly, the same function as canals, but it remained in operation until 1932.

Over the years, sections were filled for various road and rail projects and other sections of the canal were piped underground.

Today, the D&R Canal offers us a number of natural and historical resources, including 160 species of birds, wooden bridges, canal locks, historic bridge & canal houses, and former mill sites. The park can be enjoyed individually or at one of the many nature and history related programs that are offered throughout the year by the park's naturalist and historian.

The total length of the entire canal system was approximately 66 miles (106 km).

A steam tug docked on the canal in front of a Princeton hotel.

Unfortunately, some sections of the canal are forever lost. A section of the main D&R Canal in Trenton, along Mulberry Street, has been covered over (the water still flows below) and redeveloped, and is inaccessible to public use. The portion of the canal that provided access to the Delaware River in Bordentown is also abandoned. In Trenton it has been covered by NJ Route 129, which opened in 1996. Another section south of Trenton is located in Hamilton Township, Mercer County, New Jersey between the southern boundary of Trenton and the Crosswicks Creek.

Locks were used to overcome elevation differences along the D&R canal. Many of the locks are still present along the canal route; however, the lock gates have been replaced on the upstream side with small dams and water outfalls. The downstream gates have been removed, so the water in the locks is level with the water on the downstream side. Some of the locks have been buried or removed due to construction projects in the vicinity of the canal.

A number of spillways, which drained excess water from the canal into nearby waterways during periods of heavy flow, are located along the canal route. Spillways are evident as a dip in the tow path along the canal.


Image: bikinghikingwithkids.com

In 1974, most of the canal system was declared a New Jersey state park. It remains one today, and is used for canoeing, kayaking, and fishing.

A graded natural-surface trail along the side of the canal, which was the tow path that mules used to tow barges on the canal before steam powered barges, is now used for hiking, jogging, bicycling, and horseback riding. Some 36 miles (58 km) of the main canal, and all 22 miles (35 km) of the feeder canal, still exist. The feeder canal along the Delaware, being a former railroad rather than a towpath, is especially suited to bicycling. The park is operated and maintained by the New Jersey Division of Parks and Forestry.

The D&R Canal trail is a recreational trail of 77 miles (124 km) trail is made up of three segments that transverse three counties: a canal towpath from New Brunswick to Trenton; a canal towpath / rail trail from Trenton to Bull's Island; and a rail trail from Bull's Island to Frenchtown. The three combined trails together form the largest completed trail entirely in New Jersey. Much of the trail runs inside the state park. [Note: There is no direct connection between the main canal and the feeder canal paths along the Delaware River. Signed on-street connections are required to traverse the entire trail system.]

The proposed Capital to Coast Trail is planned to connect to the D&R Canal Trail.

The canal is accessible from many points along its route, with small parking areas providing access at most road crossings. One of the most scenic and popular sections of the D&R Canal state park is the segment along Lake Carnegie in Princeton, New Jersey, which features the canal on one side of the path and the lake on the other side. Another attractive section borders the Colonial Park Arboretum and Gardens in East Millstone.

The Delaware and Raritan Canal was added to the National Register of Historic Places in 1973 and the many historic canal houses where the bridgetenders lived (such as the Blackwells Mills Canal House and the Port Mercer Canal House) were listed as contributing properties.