XNP project annual report – year 3

Let's summarize the 3rd year of the Xiphophorus – Northern Platyfish Project: Covid-19 has affected our lives and of course our project activities. Most of the time it was hardly possible to travel and meet, so there were not many fish transfers. But we have learned a lot and improved in many aspects.


It is the right time to publish the numbers of fishes kept and how they have developed since the start of our project. Here are the figures as of the beginning of 2019, 2020 and 2021, respectively:

Xiphophorus meyeri Spotted: 434 - 645 - 1145

Xiphophorus meyeri Wild Type: 93 - 180 - 109

Xiphophorus couchianus: 114 - 180 - 438

Xiphophorus gordoni: 29 - 63 - 56

Xiphophorus sp. "Apodaca": 12 - 0 - 0

Xiphophorus sp. "Regio": 19 - 110 - 83

So our results are mixed, the biggest setback being the "Apodaca", which we lost. It is very complicated to find it anywhere in the world but we are working on it.

On the other hand, the total number of individuals kept by our members is constantly increasing 701 after the 1styear, 1178 after the 2ndyear and currently 1831.

Xiphophorus meyeri exceeded one thousand and Xiphophorus couchianus has more than doubled its count during the last year. These are positive examples and we need to focus on improving the husbandry of other species as well because we are still facing too many problems. Some breeding groups were reduced due to health problems or even completely lost.


The number of project members is growing as well, though not so fast due to the complications with traveling. Currently we have 28 members (compared to 23 in the previous year) from eight countries. Our new members are from Austria, Czech Republic, France and Hungary. As I wrote last year – we need to be very careful when splitting our breeding groups and any starting colony should be of a reasonable size, not just one or two pairs. Starting with more animals increases their chance to survive and breed. So we are not trying to have as many members as possible taking part in the project.


There weren't any new substantial publications regarding our activities or Northern Platyfish in general. But we have had a lively exchange of experiences and the most important information is collected for future versions of the “Northern Platyfish Husbandry Manual“.


Last year, when everything was more difficult than usual, I think that most of us really acknowledged the value of meeting other people, sharing our experiences, fish, hopes or failures with fellow aquarists. As this was nearly impossible, the purpose of our project was emphasized. The strength of such a network became evident – those who lost their fish couldn't replace them. Those who were extremely successful had to supply another tank for Northern Platyfish to be able to hold them until the Covid-19 crisis will be over. We have all experienced at first hand what conservation is about: do your best to keep the fish healthy and prospering, and share them with a trusted person when it is safe.

Future plans

There are two main objectives for our 4th year:

1. Improve husbandry and prevent/solve the health problems which affected our fishes. We need to identify the most common issues and address them in the “Northern Platyfish Husbandry Manual“.

2. Find Xiphophorus sp. "Apodaca". At least we want to verify the current numbers of fishes still surviving and get in closer contact with their breeders.


I want to thank once again all members of the XNP project. You are protecting rare species from extinction!


Markéta Rejlková

6.3.2021, Ostrava, Czech Republic

Xiphophorus – Northern Platyfish