Coho Observations [ds65]

November 2022 Version

Please do not distribute. this dataset is made available for internal CDFW use only.

This dataset depicts coho Salmon observations in California. It was developed for the express purpose of assisting with coho salmon recovery planning efforts. For the purposes of this dataset, an observation is defined as a single point in time and space where an observation pertaining to coho Salmon has been reported. A reported observation may be considered a direct observation which can be a record of an on-the-ground visual sighting whether the record is in a written report or is a recollection of an earlier direct observation. A direct observation can also be any sighting by remote electronic means such as radio telemetry and the observer is confident in it's accuracy. In addition to direct observations, an observer can cite an observation from second hand or greater information, or he or she can make a judgement that coho are present or likely to be present at a location from their own experiences or expertise. These variations on the type of observation are all included in this dataset in an effort to capture all available observations of coho in California's inland streams. Every attempt has been made by the developers of this dataset to categorize these observations so that their varying types can be easily identified by the user as a guide to making quality judgements.

As explained above, this dataset displays point locations of where coho observations have been reported, hence it contains positive observations only. However, coho may not be found on an annual basis at these locations due to natural variations in run size, water conditions, and other environmental factors. The information in this data set should be used as an indicator of coho presence/suspected presence at the time of the observation; it does not necessarily verify that coho are currently present. Conversely, the absence of point on a stream does not necessarily indicate that coho do not utilize that stream.

The point features in the dataset do not represent the maximum extent of coho on a stream; rather it is important to note that this data underestimates the actual distribution of coho salmon for these reasons; observations in themselves do not represent distribution, an observation does not necessarily occur at the upper extent of a coho's travels; the dataset will be updated as additional information is acquired, yet, time and resource constraints prevent the developers of the dataset from capturing all coho observations in existence; as environmental conditions change over time coho distribution will probably change as well. As such, any copy of this dataset is considered to be a snapshot of coho distribution at the time of release. It is impingent upon the user to ensure that they have the most recent version prior to making management or planning decisions.

This dataset was built solely from observational data: no additional data (habitat mapping, barriers data, gradient modeling, etc.) were utilized to either add to or validate the data. Several instances have been noted where a coho observation in this dataset has been recorded above (upstream of) a barrier as identified in the Passage Assessment Database (PAD). In the near future we hope to perform a comparative analysis between this dataset and the PAD to identify and resolve all such discrepencies. Such an analysis will add rigor to and help validate both datasets.

These data are compiled from a variety of disparate sources including but not limited to CDFW, USFS, NMFS, timber companies, and the public. Forms of documentation include CDFW administrative reports, personal communications with biologists, observation reports, and literature reviews. The source of each feature (to the best available knowledge) is included in the data attributes. The spatial data has been referenced to California Streams, a CDFW derivative of USGS National Hydrography Dataset (NHD) High Resolution hydrography. Where necessary, California Streams was edited to accommodate observation locations. These edits are planned to be submitted to NHD where they will become permanent features in the dataset.

Disclaimer: The State makes no claims, promises, or guarantees about the accuracy, completeness, reliability, or adequacy of these data and expressly disclaims liability for errors and omissions in these data. No warranty of any kind, implied, expressed, or statutory, including but not limited to the warranties of non-infringement of third party rights, title, merchantability, fitness for a particular purpose, and freedom from computer virus, is given with respect to these data.

Please read the metadata document completely prior to use of this dataset.

Examples of appropriate uses include:

- Coho salmon recovery planning

- Evaluation of future survey sites for coho

- Validating coho distribution models

Examples of inappropriate uses include:

- Assuming absence of a point feature means that coho are not present in that stream.

- Using this data to make parcel or ground level land use management decisions.

- Using this dataset to prove or support non-existence of coho at any spatial scale.

- Assuming that the point feature represents the maximum possible extent of coho range.

This data attempts to show the latest available observations for coho Salmon in California, where such information is known. Please note this data is a work in progress and is subject to change/update as new information becomes available. This data contains observations currently entered into ASOD and should NOT be assumed to be all known observations. It is complete as far as time and resources have enabled it to be at this point in time, but as a result of these limitations underestimates the actual distribution of coho salmon observations. Its purpose is to be a guide for future management and planning.

Spatial data has been mapped to USGS National Hydrography Dataset (NHD) High Resolution hydrography. Where NHD High Resolution is not available, stream features were digitized at NHD standards to accommodate observation features. This is NOT an all-inclusive data set of coho salmon observations, as additional streams may exist that have not been mapped. Similarly, not every stream that has been mapped has been studied rigorously enough to be definitively ruled out as a coho stream. Because of the inherent inaccuracies involved when mapping data at different scales, moving point features generated from coordinates or digitizing to the hydrography, translating data from textual descriptions as well as from personal interviews, this dataset is not accurate enough to support parcel level analyses; it is suitable for watershed level uses only.

All users of this data should seek the assistance of qualified professionals such as surveyors, hydrologists, or fishery biologists as needed to ensure that such users possess complete, precise, and up to date information on coho salmon distribution and water body location.