How fast can trout swim

We fed the fish daily with commercial Trout feed, but food was withheld for 24 h in advance of a swim trial. To initiate a trial, water was introduced to the flume and allowed to reach steady conditions 45—60 min. On-site hydraulic measurements, corroborated with a gradually varied flow hydraulic model, characterized the flow environment in the flume for each trial.

We used a graduated rod to measure the water depth at each grid interval over the length of the flume and continuously logged flow depth in the headwater and tailwater tanks with TruTrack WT-HR data loggers TruTrack Ltd. We corroborated inflow rate values with a U.

Geological Service method in the flume itself Rantz et al. Together, these observations resulted in estimates of the flow depth and bulk water velocity at each 0. For each trial indicated in Table 1 , we placed the subset in the tailwater pool at the downstream end of the flume. We did not coerce fish to enter the flume, nor did we coerce or intentionally spook them during any part of the swim trial.

Each trial lasted 4 h, a duration based on pilot studies that showed this was sufficient time for fish to make multiple attempts, explore, and often ascend the length of the flume. We recorded continuous video footage from all cameras over the duration of each trial as fish moved throughout the flume. We distilled the movement of individual fish position in the flume versus time from the camera array video footage from the video footage the distilled data are in the Data S1, Supplemental Material.

We processed the video streams by examining these still images and noting the spatial position of each fish in successive time-stamped images. Overall, there were 89 observations unique combinations of entries in the columns labeled fish and event in Data S1 of fish exhibiting forward facing direction and forward travel both species combined , as shown in Figure 2. Missing data are the result of camera malfunctions or multiple fish crossing paths through the frame, making it impossible to uniquely identify fish in subsequent frames.

For swim events with missing observations, it is assumed that the fish would have continued along a path similar to the path they were on while available for observation. Because of the relatively constant nature of the swim events exhibited in these data, this assumption is reasonable Figure 2.

To account for dependencies within multiple observations during the same swim event, which varied between 4 and 21 observations, we calculated the average swim velocity for each swim event Figure 3.

We placed Rainbow Trout Oncorhynchus mykiss or Westslope Cutthroat Trout Oncorhynchus clarki lewisi in the outlet pool of an open-channel flume in Bozeman, Montana, in and allowed fish to enter and traverse the flume volitionally.

The graph shows individual observations of fish swim velocities relative to the water, v fij , for each swim event for Rainbow Trout salmon-colored lines and Westslope Cutthroat Trout blue lines. Although observations are point-wise, the connecting lines show the dependence within a swim event i.

The box plots show the median, the first quantile, the third quantile, and fences for the unweighted observations. The symbol size for each fish corresponds to the weights used in the regression analysis to estimate the weighted overall average swim speeds for each species. We calculated the weights as the total number of observations divided by the variance in observations sample variance from an individual swim event. For Rainbow Trout, we estimated the overall average swim speed to be 0.

These intervals provide a range of plausible swim speeds for the fish in this study. The maximum observed swim speed within an 0. Fish swim studies have inherent limitations. This study represents the first that we are aware of in which swim trials were volitional in an open flume for two species of Trout.

We took the fish used in the study from two specific streams in Montana, and any inference beyond the Trout used in this study should be approached with caution. We only performed the volitional trials under one hydraulic challenge. The range of size length of the fish tested was relatively narrow because we captured the fish in the wild for the study, enough so that no attempt to characterize swim speed by fish length was made.

Lastly, we implanted the fish with passive integrated transponder tags before the experiment. The maximum swim speed observed in this study for Westslope Cutthroat Trout 3. For Rainbow Trout, the maximum observed swim speed in this study 2.

The maximum Rainbow Trout velocity in all studies reviewed in the preparation of this report was 8. For a comparison to other Trout species, Mesa et al. For Rainbow Trout, the overall average swim speed observed in this study was estimated to be 0. The results of this study should not be compared directly with results of respirometers studies, but it is interesting to note results of the respirometer studies when the fish lengths and water temperatures of the tests were reasonably similar.

Bainbridge reported a U crit of 0. The average Rainbow Trout swim speed observed in our volitional trials is within the range of U crit values reported in previous respirometer studies that had comparable fish lengths and water temperatures. One major design goal of fish passage structures is to ensure that Trout and other fish species are able to easily pass upstream without exhaustion.

These guidelines are recommended for culvert installations using a hydraulic design approach, which creates specific water depths and velocities for a range of fish passage flows in culverts. The results of our volitional trials fall within these values for conservative passage design: Rainbow Trout ascended the test flume at overall average swim velocities in a plausible range from 0.

Practitioners using swimming abilities to infer passage probability, whether assessing structures such as culverts , identifying barriers, or purposefully creating barriers are advised to synthesize the relevant data specific to their application and apply conservative values to ensure the success of specific goals. The results from this study provide information to a growing body of Trout swimming ability literature; we characterized the swimming performance of similar-sized individuals of two Trout species, Rainbow Trout and Westslope Cutthroat Trout, under specific laboratory test conditions.

Passage probability models are only as good as the representative swimming data for the specific physiological aspects of a species and environmental conditions surrounding the observation. Although our study was limited in scope and more studies investigating the leap and velocity metrics associated with identifying barriers for Trout species would be valuable, our results provide new information on the swimming ability of wild Trout that can be used to refine passage models.

Please note: The Journal of Fish and Wildlife Management is not responsible for the content or functionality of any supplemental material. Queries should be directed to the corresponding author for the article. Data S1.

Supplemental file that archives the experimental observations of Rainbow Trout Oncorhynchus mykiss or Westslope Cutthroat Trout Oncorhynchus clarki lewisi that we placed in the outlet pool of an open-channel flume in Bozeman, Montana, USA, in and that we allowed to enter and traverse the flume volitionally.

Each observation of a fish traversing a 0. The file is in Excel format, there are 3, rows by 18 columns in the data set, and the file is annotated to fully describe the contents of each column.

Each row in the file includes fish identifiers, fish length, water velocity, fish ground speed, fish speed relative to the water, water temperature, and categorical variables that aid in automating the analyses. Data S2. An annotated text file containing the R code used in the swim speed analysis of Rainbow Trout Oncorhynchus mykiss or Westslope Cutthroat Trout Oncorhynchus clarki lewisi that we placed in the outlet pool of an open-channel flume in Bozeman, Montana, USA, in and that we allowed to enter and traverse the flume volitionally.

The R code performs statistical analyses and prepares the graphs that summarize the analysis. Reference S1. Fish passage through culverts. Reference S2. Water crossings design guidelines. Reference S3. Bell MC. Within a few seconds it leapt again, about 50 feet upstream. It happened so fast, Hammer's line was still pointing downstream. The line then ripped out of the water, sizzling upriver like a fast-burning fuse just as the fish leapt again — several yards downstream of Hammer, whose head was on a swivel, snapping left-right-left.

Over the next minute or so, I don't believe the line was ever pointing to the spot where the fish actually was. When his line finally snapped it sounded like a gun shot. I still don't know where he got that statistic, but I can tell you this: The fish Hammer hooked was moving exponentially faster than the 23 mph attributed to rainbow trout by WikiAnswers.

Another site claims salmon can swim at 45 km per hour technically, rainbow trout are pacific salmon, as indicated by the designation onchorynchus, but based on my experiences with each, I tend to believe steelhead are faster than kings, silvers, chums, etc.

And quite a bit faster than brown trout. In-Fisherman ran a comparative chart years ago that claimed steelhead could swim at 35 mph, but that's probably an educated guess from a steelhead fisheries manager that tried to clock one with a speed gun. Personally, I think the only way to know for certain is to have an orca chase one past a radar station. Dolphins are, of course, mammals, not fish, but they're probably the fastest things in the sea. Certain species of shark are among the fastest fish in the sea.

Like tuna, they can purportedly achieve bursts of 50 mph or so. Part of the reason for this enhanced color perception is that the yellow to blue wavelengths of light travels better in water than in air.

Having the eyes on the side of the head also gives the Rainbow Trout a different perspective on the world. This placement of the eyes allows the fish to see to the front, sides and most of the way behind.

The only blind spots are immediately behind and directly below the fish. Upward and directly in front, the fish has depth perception or binocular vision as both eyes come into play.

Toward the rear and to either side, only the eye on that side is used and the trout has monocular vision without depth perception. Viewed from below, the water surface reflects light when viewed at an angle. So the trout can only see the upper world through a small round 'window' that is directly above and has a diameter that is about twice the depth of the fish. A trout cruising 10 feet down can only 'see' a dry fly presented within about 20 feet of its location. No, the Rainbow doesn't have an external ear yet it can hear sound better than almost all land animals.

The trout's three-chambered 'internal' ear picks up sound very well. If you drop your glasses in the bottom of the boat, a trout across a large lake will easily hear that sound and the nearby trout will probably be spooked into a non-feeding phase by the noise. The ear also serves as an organ for balance. Land animals use fluid in the ear for balance.

In a fluid environment, the trout uses calcified stone in each ear chamber to help it tell up from down and left from right. The senses of taste and smell are particularly well developed in the Rainbow Trout. They are better developed than the legendary Bloodhound and about times more sensitive than these senses in a human. It is believed that Rainbow Trout, steelhead and salmon all of the scientific Order of Oncorhynchus use taste and smell to help locate the waters of their original spawning streams.

A Rainbow Trout can smell the difference between two aquatic plants of the same species that are side by side. It can even taste the difference between two species of Chironomid and thus will have a preference for one species over another.

Rainbow Trout are very sensitive to differences in ph, salinity and the differences in amino acids as found in their food sources. It is thought that the Rainbow may even have taste and smell sensors on parts of its body other than in the nostrils and mouth and that these may actually help the trout in locating its food. Would you believe that we have yet to come to the most astounding aspect of the trout's senses?

Besides the normal touch sense that most animals have, the Rainbow Trout has what scientists are calling the "Distant Touch" sense. The scientists aren't exactly sure how this all works but here are a few of the known details.

Water is times denser than air. In part, this is why the trout can hear, smell, taste and see color so well. As a denser medium, water carries the mechanisms for sensory input much better than air. The senses of touch and perception are no different. The Rainbow can feel and perceive distant objects or movements about time's better than we can and may even have a form of echolocation. Imagine that someone drops a ball of cheese at the other end of a football field. Other than the fact that you saw it drop, you probably wouldn't know that it had happened.

At that distance, with its eyesight, a Rainbow Trout wouldn't see the cheese ball drop. However, underwater it could 'feel' the concussion of the cheese ball hitting the ground, hear the sound it makes when it hits and may even be able to smell and taste the cheese shortly after the hard outer cover breaks.

It is even possible that, through echolocation, the trout could tell us exactly where the cheese ball hits in the end zone. A person capable of doing the same would be considered to have ESP. First some background. In the characteristic undulatory swimming motion of fish, muscles contract sequentially along the body to generate a backward-moving wave of body bending. This pushes against the water and produces thrust. But exactly how this thrust arises is something of a puzzle.

His idea was that each segment generates drag, a resistance to movement. As the segment undulates, the drag is greater in a perpendicular direction to the body than parallel to it. The result is thrust in the parallel direction, or forwards. This idea is known as resistive force theory. But in , a British mathematician, James Lighthill, put forward a different idea in which the dominant effect is the inertia of the water.

This allows a flat plate to generate thrust by waving with a small amplitude. This is known as elongated body theory. The key difference between these theories is the type of force generated. For Taylor, it is resistive force, which acts in the opposite direction to movement of a body but is in phase with that velocity.