This page explains what cookies are, which kinds may be used here, what each category is for, and how to control them from your own browser. It is a companion to the privacy policy, which covers the wider question of what information is collected, how long it is kept and which rights apply to it. Between them, the two documents are meant to describe the whole picture without either one repeating the other.
The general position is that a reference site should ask for as little as possible. Reading a species profile or comparing two animals requires no account and no stored identity, and where a choice can be carried in the link rather than saved on your device, that is the route taken.
What a cookie is
A cookie is a small text file that a site, or a service that site uses, asks your browser to store. On a later visit the browser may send that file back, which lets the site recognize a returning browser or remember a setting. Cookies cannot read other files on your device, cannot run programs and cannot see anything you have not given to the site that set them.
Cookies are distinguished by who sets them and how long they last. A first-party cookie is set by the site you are reading. A third-party cookie is set by a different service whose content or measurement appears on the page. A session cookie disappears when you close the browser, while a persistent cookie remains for a stated period unless you clear it earlier.
Categories used here
Cookies on this site fall into four categories. Strictly necessary cookies support delivery and security and cannot meaningfully be refused without the site failing to work. Preference cookies remember a setting you chose. Measurement cookies help count page views and understand how readers move through the catalog. Advertising cookies, where third-party advertising is present, are set by those services to select and measure the advertisements they deliver.
The last two categories are the ones a reader is most likely to want control over, and both can be limited through the browser controls described below or through the opt-out routes set out in the privacy policy. Nothing in either category is necessary for reading a profile, running a comparison or following a citation. Refusing them changes what is counted and what advertising is selected, and changes nothing about the material on the page.
The four categories
- Strictly necessary: page delivery, load balancing and protection against abuse
- Preference: remembering a display or unit setting you chose
- Measurement: aggregate statistics on which pages are read and how readers arrive
- Advertising: set by third-party advertising services to select, cap and measure advertisements
Choices carried in the link
Most of what you select while reading this site is not stored on your device at all. The two species in a comparison, the group or ocean filters applied to the catalog, and the sort order you chose are all carried in the address of the page you are looking at. Nothing about those choices needs to be remembered between visits, because the page itself already describes them.
This has a practical benefit beyond privacy. A comparison you built can be bookmarked, sent to someone else or reopened months later and will show exactly the same pairing, without depending on anything saved in your browser. A filtered catalog view behaves the same way. Clearing your cookies does not disturb any of it.
Third-party cookies
Cookies set by measurement or advertising services belong to those services, not to this site. They are governed by the operator's own privacy policy, and their contents are neither readable nor accessible here. An advertising service may use such cookies to limit how often the same advertisement is shown, to record whether one was seen, and to personalize what it delivers based on information gathered across many sites.
The privacy policy sets out how to limit personalized advertising, including the ad settings offered by advertising services themselves, the industry opt-out pages that cover many participating services at once, and browser-level controls. Those options reduce personalization and tracking. They do not remove advertising from the pages that carry it.
Controlling cookies in your browser
Every major browser provides cookie controls, usually under privacy or site settings. Common options include blocking third-party cookies while allowing first-party ones, clearing all stored cookies immediately, deleting them automatically when the browser closes, and refusing storage for particular sites. Private or incognito windows discard everything stored during the session when they close.
These controls are set per browser and per device. A choice made on a laptop does not carry to a phone, and a choice made in one browser does not apply in another. Clearing cookies also clears any opt-out preferences that were themselves recorded as cookies, which occasionally means an opt-out has to be set again after a cleanup.
Where the controls usually live
- Chrome: Settings, then Privacy and security, then Third-party cookies
- Safari: Settings or Preferences, then Privacy
- Firefox: Settings, then Privacy and Security
- Edge: Settings, then Cookies and site permissions
- Mobile browsers: the same menus, generally under Settings and Privacy
If cookies are blocked
Blocking cookies will not stop you from using this site. Species profiles, the catalog, guides and the comparison view all work without anything stored on your device, because none of that content depends on recognizing a returning reader. Citations and links behave normally, filters continue to apply, and a comparison remains shareable because the pairing travels in the link rather than in storage. Nothing is hidden behind a preference that has to be remembered.
The visible effects are small. A display or unit preference will not persist, so it may need to be set again on a later visit. Measurement will undercount, which affects the statistics available to the editors rather than anything you see. Where advertising is present, blocking may leave it less relevant or, in some cases, prevent it from loading. None of this changes what any page states.
Do Not Track and Global Privacy Control
Browsers can send signals expressing a privacy preference. The older Do Not Track header was never adopted consistently and most services now disregard it. Global Privacy Control is a more recent signal that carries legal weight in some United States jurisdictions, and services that honor it treat it as an opt-out request from that browser.
Because measurement and advertising cookies are set by third-party services rather than by this site, how a given signal is treated depends on the practices of the service receiving it. The browser controls and opt-out routes described above are the more dependable approach, since they take effect regardless of whether a service chooses to honor a signal. Both can be used together, and using them together is the stronger option.
Updates to this policy
This policy will change if the categories in use change, if a new measurement or advertising service is introduced, or if the law requires a different disclosure. The revision date at the foot of the page always reflects the current version, and substantive changes will be described on the page rather than made quietly. A policy that shifts without notice is worth less than no policy at all.
Questions about anything on this page, including what a particular category covers in practice or how a control behaves in a specific browser, can be sent to [email protected]. Questions about what information is collected more generally, how long it is kept and which rights apply to it are answered in the privacy policy, which is the more complete document on those subjects.