Fish can climb... ladders?

Australia's waterways are home to a diverse array of fish species, each playing a vital role in maintaining the ecological balance of our aquatic ecosystems. One key challenge these fishes face is the presence of dams and weirs that obstruct their natural migration routes.

How can us humans help our fishy friends continue their journey – the fish ladder.?

The concept of a fish climbing a ladder might sound amusing, but fish ladders are engineered designed structures that help fish navigate obstacles in their natural habitat. Fish typically "climb" these ladders by swimming upstream through a series of interconnected pools or stepped sections, allowing them to reach their spawning grounds with minimal disruption.??

Here's how it works:?

Structure Design: Fish ladders are constructed alongside dams, weirs, or other barriers in rivers or streams. They consist of a series of steps, pools, or other configurations that create a pathway for fish to move upstream.?

Flow of Water: Water is directed to flow through the fish ladder, simulating a natural stream or river environment. The flow of water helps guide fish along the ladder.?

Pools and Resting Areas: Fish ladders often include pools or resting areas at each step. These serve as resting spots for fish, allowing them to pause, regain energy, and adjust to changes in water pressure.?

Attraction Mechanisms: Fish ladders may incorporate features such as weirs or other flow inducers to attract fish to the entrance. These mechanisms mimic natural conditions and entice fish to enter the ladder.?

Upstream Navigation: Fish instinctively swim upstream for various reasons, including spawning. In a fish ladder, they navigate from one pool or step to another, essentially "climbing" through the structure. The design ensures that fish can overcome obstacles and reach their desired upstream destinations.?

Exit to Upstream Habitat: At the top of the fish ladder, there is an exit that leads fish to the upstream habitat they are seeking. This could be a spawning area, feeding grounds, or other essential locations in their life cycle.?

Fish ladders are crucial for maintaining healthy fish populations and preserving biodiversity in rivers and streams. They provide a solution to human-made barriers that might otherwise hinder the natural migration and life cycles of fish species. While it may not be a literal climb like you'd imagine, the fish's journey through a fish ladder is fascinating.

Our ViridAU environmental team, comprising leading scientists, managers, and engineers, excels in technical environmental assessments spanning water, land, air and acoustics.

Get intouch today www.virid.au