About: Contents of Current Video Library Alevin to Fry Development

The library contents show the development of Rainbow trout eggs on their way to becoming rainbow trout. Each folder contains one or more video files showing how Eggs/Alevins behave at different stages in the process:

Delivered Eggs Hatched Eggs (Alevins 0% developed)Fry (100% developed). 

We use the day the eggs hatch as the zero point in the % developed scale. The amount of time between egg delivery and hatch will depend on individual aquaria temperature. However, unlike the day scale, the % development should be independent of different aquaria running conditions.

You will note that there are no data for eggs in 2020 because all eggs were hatched on delivery. However, if we know a hatch date we can calculate the  swim-up date.  In 2021 our “eggs” were crammed into tightly bound sacks which, besides hatched Alevins, had about 5 dead eggs.   I believe this tight packing was extremely stressful to the surviving Alevins because the videos for the immediate days after delivery showed them to be sluggish compared to previous years. 

To best view the developmental changes in the alevin, first download all the contents of the library folder to your computer. If you're unsure how to download files from Google Drive, please see the instructions at the bottom of this page.

 Put the files into a folder on your computer labeled “Alevin video library”. Move the file “Index” to your desktop and open. Click on any of the links showing video for a % development and play with your computers video player. The changes between 10% changes may be subtle. Arrange the files on your computer screen and compare with your classroom aquarium. Use our SU planner (available here) to determine what date your alevins should be xx% developed. Compare your Alevins with those shown in the video library. Remember not all alevins will be at the same degree of development but your observations should show something close to the library videos.

About time lapse video in the Nest system:

Unlike time lapse photography in cameras, video is activated by motion in a predefined area.

In our aquaria two areas are defined: Gravel and Above the gravel.   A Motion event in a time period initiates the video, which is saved in the “cloud”,  Viable eggs before hatching show enough movement to activate video so that the time lapse over a long period of time appears to be continuous  provided that there are no periods of complete inactivity. Thus, a continuous many hour time lapse is possible ad long as there is some detectable motion. Any extended periods of no movement, or loss of Wifi signal, breaks the time lapse video steam into separate clips which we have avoided presenting in this library.

If you publish any of the files from this library you must identify the source as Jim Scherer @ Grizzly Peak Fly Fishers.


Current (June22) Video Library of Alevin to Fry Rainbow Trout Development:

How to download files from google drive:

Clicking any of the above links will take you to the sub-folder of the Updated Alevin Library on google drive and list the contained videos. 

To download an individual video, hover over the video with your cursor and click on the download icon that appears in the upper left corner, see yellow circle in below image.

Alternatively, you can select "Download All" from the upper right corner to download all contents of the current folder, see yellow oval in below image.

This applies to any individual file or folder in the Updated Alevin Library.

If you'd like to download the whole Updated Alevin Library at once, navigate to the Updated Alevin Library folder and select DOWNLOAD ALL from the upper right corner:

If you are logged into your google account, you will have different options.  Locate the drop down menu at the file path, as shown in the below image:

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