A very special picture - Altum angelfish in their biotope

The photo was taken at a depth of 50 cm in the Rio Atabappo in Colombia, which forms part of the border with Venezuela. What made it special was the water temperature of 32.7 °C! It was the highest water temperature we have ever measured in natural waters containing fish in South America on our JBL expeditions. But the photo contains even more interesting information for us aquarists: That the angelfish share their habitat with flag cichlids (Mesonauta festivus). The plants in the picture are not underwater plants. In Rio Atabappo there are no aquatic plants under water at all. If you find anything green under water it’s leafy broken-off branches, or overwater plants forced to survive under water for a while due to a high water level. The water colour shows the typical blackwater of the region with no measurable general or carbonate hardness, a conductivity of 19 µS/cm and a strongly acidic pH.

Just how dangerous are crocodiles for snorkelers?

While snorkeling in our ornamental fish habitats, we may encounter crocodiles. In South America, this is 99.9% unproblematic, as they are harmless caimans that are more afraid of us than we are of them. Only the black caiman can be really dangerous, but that's exactly why they have been practically wiped out.

In Australia, the situation is different. Two types of crocodiles live there: The freshwater forms, called freshies, and the saltwater crocodiles, called salties. The freshies are usually harmless and when encountered they retreat or threaten by opening their mouths. If you then make an orderly retreat you’ll be able to leave the water with all your limbs intact. This is not the case with salties. Even their maximum size of about five meters is impressive. Waters where saltwater crocodiles live are marked with warning signs in three languages. Fatal is the fact that these lizard-like reptiles can be encountered hundreds of kilometers inland from Darwin on the north coast! At high tide, they advance far inland in the rivers and then, as the water level recedes, find themselves in pools where they really have no business being. And when they are hungry too...

Find out more about Colombia here:  Expedition 2022 Colombia I

© 25.09.2022
Heiko Blessin
Heiko Blessin
Dipl.-Biologe

Tauchen, Fotografie, Aquaristik, Haie, Motorrad

Comments

A word about cookies before we continue

The JBL Homepage also uses several types of cookies to provide you with full functionality and many services: We require technical and functional cookies to ensure that everything works when you visit this website. We also use cookies for marketing purposes. This ensures that we recognise you when you visit our extensive site again, that we can measure the success of our campaigns and that the personalisation cookies allow us to address you individually and directly, adapted to your needs - even outside our website. You can determine at any time - even at a later date - which cookies you allow and which you do not allow (more on this under "Change settings").

The JBL website uses several types of cookies to provide you with full functionality and many services: Technical and functional cookies are absolutely necessary so that everything works when you visit this website. In addition, we use cookies for marketing purposes. You can determine at any time - even at a later date - which cookies you allow and which you do not (more on this under "Change settings").

Our data protection declaration tells you how we process personal data and what purposes we use the data processing for. tells you how we process personal data and what purposes we use the data processing for. Please confirm the use of all cookies by clicking "Accept" - and you're on your way.

Are you over 16 years old? Then confirm the use of all cookies with "Noticed" and you are ready to go.

Choose your cookie settings

Technical and functional cookies, so that everything works when you visit our website.
Marketing cookies, so that we recognize you on our pages and can measure the success of our campaigns.

PUSH messages from JBL

What are PUSH messages? As part of the W3C standard, web notifications define an API for end-user notifications that are sent to the user's desktop and/or mobile devices via the browser. Notifications appear on the end devices as they are familiar to the end user from apps installed on the device (e.g. emails). Notifications appear on the end user’s device, just like an app (e.g. for emails) installed on the device.

These notifications enable a website operator to contact its users whenever they have a browser open - it doesn’t matter whether the user is currently visiting the website or not.

To be able to send web push notifications, all you need is a website with a web push code installed. This allows brands without apps to take advantage of many of the benefits of push notifications (personalised real-time communications at just the right moment).

Web notifications are part of the W3C standard and define an API for end user notifications. A notification makes it possible to inform the user about an event, such as a new blog post, outside the context of a website.

JBL GmbH & Co. KG provides this service free of charge, and it is easy to activate or deactivate.