The Fence Post

There are various types of woven wire mesh used at the Franklin Park Zoo in Boston and Stone Zoo in Stoneham, Massachusetts. 

When strength, height, and larger openings are required, woven fences that are galvanized are used. Deer and wildlife fence is a popular choice. Available in a 96" height, the mesh has graduated openings between the horizontal wires with smaller openings at the bottom of the fence. Vertical stay wires are 6" apart. 12½ gauge high-tensile wires and fixed knot construction make it very strong. Class 3 galvanizing ensures a long lifetime.    

This is a versatile fence that can be used for both four-legged and two-legged animals. 

Another type of fence used is 2" x 2" woven non-climb mesh. Made from lighter 16 gauge wire, it can be used to make enclosures for smaller animals and birds. The top and bottom wires are heavier 14 gauge. The square deal knots that are used hold the horizontal and vertical wires securely in place, yet the fence has some flexibility which allows it to conform to the irregularities of the ground. The mesh has an open feel and is easy to see through. In the picture below the fence is used for the vertical sides of the display.

These are some of the different types of fencing used at the two zoos. What types of wire meshes have you observed at the zoos you have visited?

Easy Counting

A counting fence is a live trap fence used in rivers to capture salmon and trout. This results in an accurate count of the number of fish present. Sometimes V-shaped, it extends across the river's entire width. As the fish swim up or down the river they are caught in a box-like trap structure where they can be easily counted.

The following video shows a counting fence on Morrison Creek the day after heavy rains. The fence has been dislocated somewhat by the higher water level. It gives you an idea of how this fence works.

River Counting Fence The counting fence is a live trap fence which is composed of rebar and is v-shaped. It extends across the entire length of the river with a box-like/trap structure in the centre. It's function is to trap and count adult salmon and trout that return to the river to spawn

Old and New 

On the Babine River in British Columbia, a counting fence has been in place since 1946. In early July, 4' x 7' aluminum panels that make the fence are installed along the 330' permanent frame. 6' x 8½' trap boxes are installed next. Then the count begins.

A newer design is a floating fence. When leaves, branches, or logs float downstream, the fence submerges so that the debris slides over the fence rather than getting caught and clogging the fence causing a blowout. The fence is removed when not in use.

While we're on the subject of counting fish, here's some great info on tracking Pacific Northwest salmon. 

Have you ever seen a counting fence in use?

A Power Plant Accommodates Turtles

Turtle Fence is being used to keep turtles out of construction areas.

The huge Ivanpah 440-megawatt solar power electric generating facility in south-eastern California is being surrounded by more than 39 miles of turtle fence. Why? Because before construction can begin on the site, all desert tortoises must be removed. And after completion, turtles will not be able to re-enter the site. The desert tortoise is a threatened species and considered vulnerable. They live their rather languorous lives in burrows anywhere from 3 to 10 inches deep, also in rock shelters or pallets. This is to minimize exposure to extreme temperatures, minimizing loss of water, and keeping their body temperature stable. Soil type is important to them for the purpose of den construction and nutrition, preferring alluvial fans, washes, and canyons. Appropriate burrow sites aid their population and their fidelity to their nesting grounds is strong. 

Galvanized Mesh

What has been selected as the best mesh to use for the purpose of assisting in this project? Locally sourced, US-made galvanized after weld, 16 gauge, 1" x 2" wire mesh that has been welded into 36" x 100' rolls. After the welding process, the mesh is drawn through a bath of molten zinc. The wires, including the welded areas, are covered with a thick corrosion-resistant coating. The welded wire turtle fence will last for years.

During installation, a portion of the fence is buried in the ground to discourage burrowing. The above-ground portion is tall enough to prevent the turtles from climbing over the fence. In this case, tortoises are being protected by being kept out of an area.

Here's some background on the situation:

Do you think this is a good solution?

Vinyl Coating  Questions and Answers

Q: What should you look for when you want to use a wire mesh to build a fence with superior qualities?

A: Vinyl-coated welded or woven wire mesh or fence.

Q: Why are these products superior?

A: Because they share the following four characteristics:

1. Vinyl-coated meshes are more durable.

• The vinyl coating gives extra rust protection, sealing the galvanized wire underneath
• Coated wire will last far longer than wire that is only galvanized

2. Vinyl-coated fences are more attractive.

• Color masks the utilitarian and commercial appearance of plain galvanized mesh
• A vinyl-coated wire fence will dress up your property
• Black color is virtually invisible from a distance and will not detract from your view

3. Vinyl-coated wire is safer.

• Vinyl cushions the wires
  
• Areas that may have sharp edges, like the top and bottom of the fence, are protected and sealed
  
• There is a lower risk of injury from contact with the fence--safer for animals

4. Vinyl-coated fencing is cost effective.

• Using vinyl-coated welded or woven fence reduces the need for frequent replacement
  
• The higher initial cost can be offset by the labor and material cost of more frequent repairs and replacement of galvanized material

Can you think of more reasons why or situations where it would be better to install a vinyl-coated fence instead of a galvanized fence?

Here's a look at the mesh in production: 

Waste Not Technologies/Close the Loop

Here's something different, practical, and timely! Plastic bottles are recycled and made into post and rail fence designed to replace wood sections. Watch the process in this video.

Watch this next video for more information about Waste Not Technologies and its manufacturing process.

Waste Not Technologies and Close the Loop are two companies that are doing their best to do something creative and practical when it comes to the problem of plastic waste in our landfills and oceans. 

Would you be willing to try using these products?