November 11, 2020

The trail of Paxyodon syrmatophorus

On a windless night, in shallow, clear and still water, it was possible to observe the underwater trajectory of a specimen of Paxyodon syrmatophorus through the track it left in the sand when moving.




The specimen was removed from the water for the photo and then returned to the same location in the same position.


This event was recorded in


Other specimen nearby was moving also, as shown in the following photos





This observation was made in the Amazon region, on the right bank of the Tapajós River, in a place called Jutuba

Posted on November 11, 2020 06:48 PM by nelson_wisnik nelson_wisnik | 1 comment | Leave a comment

February 14, 2020

Project "The World Water Day 2020 - BioBlitz March 21 to 22"

"World Water Day is an annual UN observance day (always on 22 March) that highlights the importance of freshwater. The day is used to advocate for the sustainable management of freshwater resources. World Water Day is celebrated around the world with a variety of events. These can be educational, theatrical, musical or lobbying in nature." [1]
It is well known that the forms of live we deal with in the earth are all, or nearly all, dependent of the water. Being so, we needed to choose some few to catalog in the World Water Day. We avoided the obvious species that expend all their lives in the water (fishes, algae, for exemple), in favor of some that have have relation to water either in time or space, are around us, and do not demand sophisticated equipments to observe them.
"Amphibians are small vertebrates that need water, or a moist environment, to survive.
The species in this group include frogs, toads, salamanders, and newts. All can breathe and absorb water through their very thin skin." [2]
"Most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on earth. Cacti show many adaptations to conserve water." [3]
"Bromeliads often serve as phytotelmata, accumulating water between their leaves. The aquatic habitat created as a result is host to a diverse array of invertebrates, especially aquatic insect larvae. These bromeliad invertebrates benefit their hosts by increasing nitrogen uptake into the plant. [4]
"Nymphaeales, the water lily order of flowering plants, is found in quiet freshwater habitats throughout most of the world.
All plants of the Nymphaeales order are aquatic." [5]

https://www.inaturalist.org/projects/the-world-water-day-2020-bioblitz-march-21-to-22
https://www.inaturalist.org/projects/the-world-water-day-2020-amphibians-bioblitz
https://www.inaturalist.org/projects/the-world-water-day-2020-cactuses-bioblitz
https://www.inaturalist.org/projects/the-world-water-day-2020-bromeliads-bioblitz
https://www.inaturalist.org/projects/the-world-water-day-2020-nymphaeales-bioblitz

[1] https://en.wikipedia.org/wiki/World_Water_Day
[2] Animal Encyclopedia, National Geographic Book (C) 2012
[3] https://en.wikipedia.org/wiki/Cactus
[4] https://en.wikipedia.org/wiki/Bromeliaceae
[5] https://www.britannica.com/plant/Nymphaeales

Last year's BioBlitz results are in
https://www.inaturalist.org/journal/nelson_wisnik/22703-project-the-world-water-day-2019-bioblitz-march-22-to-24

Posted on February 14, 2020 12:58 AM by nelson_wisnik nelson_wisnik | 5 comments | Leave a comment

December 5, 2019

Furnarius rufus, the builder

Furnarius rufus (Rufous Hornero) is a remarkable species, a builder, its nest is a solid construction made of adobe. An interesting feature of the nest is its shape, it has a corridor at the entrance that protects residents from wind, rain and, especially, predators. The nest is robust and durable, lasting for years.





Due to its durability, it is used to breed many generations not only of Furnarius, but also by other species of birds and, sometimes, by wasps.
Occupations that I have already observed
by Progne tapera
https://www.inaturalist.org/observations/35828990
https://www.inaturalist.org/observations/142289629
by Sicalis flaveola
https://www.inaturalist.org/observations/34710277
by Forpus xanthopterygius
https://www.inaturalist.org/observations/18471437
https://www.inaturalist.org/observations/18400742
https://www.inaturalist.org/observations/37318191
https://www.inaturalist.org/observations/142367082
by Polybia jurinei
https://www.inaturalist.org/observations/13085796
by Myiodynastes maculatus
https://www.inaturalist.org/observations/138851329

To access the observations, "explore" filtering for the person's name "nelson_wisnik" and the Description/tags "nest occupation". You are welcome.

Posted on December 5, 2019 03:14 AM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment

July 11, 2019

the amazing Vanellus chilensis nest

There is an interesting fact about the eggs of the "Vanellus chilensis", its shape. 
they do not have the common shape of eggs, they have a sort of "conical" shape with two importante consequences:
First, the conical shape alows better arrangement together; 
Second, since the "nest" is, in fact, the bare terrain soil, whitout any constraints to keep then together, the conical shape avoids them to roll far from assumed posicion of the "nest".

Posted on July 11, 2019 10:12 PM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment

July 8, 2019

a look at citizen science in Latin America

Having participated in the "Workshop: Science of the Citizen of Biodiversity in Latin America" ​​held in September of 2018 in Mexico City, I met many people who taught me new ways to observe biodiversity, not only through individual specimens, but also through interactions between species, the "web of life", leading me to admire them for their competent and efficient work.
Even before going to the Workshop, I processed some simple statistics to situate myself (as one of the representatives of Brazil) in relation to the other countries that would participate in the event. I found that our performance, at least as far as the use of the iNaturalist platform is concerned, is very poor compared to the other Latin American countries.
Back in Brazil, I made several contacts with people involved with different forms of life, in universities, a journal of scientific divulgation, study groups, science citizens, government institutions and individuals, presenting them to the iNationalist, stimulating them to register their observations in a broad-spectrum database.
I updated the statistics to present them to the iNaturalist community. These statistics were prepared for the 15 Latin American countries that were represented at that Workshop. The data were obtained on July 7 counting only verifiable observations. The results are very interesting.

To compare the performances of countries with such different populations, from 4 million (Panama) to 209 million inhabitants (Brazil), it was calculated the number of observers per million inhabitants. The comparison is shown in figure 1.




Figure 1

In some sense, this statistic illustrates the engagement of the population with citizen science and the use of the iNaturalist platform. [Please, see Post Scriptum bellow]

To compare the performances of countries with such different areas, from 51,000 km² (Costa Rica) to 8,512,000 km² (Brazil), it was calculated the number of observations per 1,000 km². The comparison is shown in figure 2.



Figure 2

One can think of the influence of population density to access the sites to make the observations, but no correlation was found in this sense. It may be a result of the attention and the experience of the citizen scientist when he or she is in the field. [Please, see Post Scriptum bellow]

Comments are welcome.

Post Scriptum
The comments of "aztekium_tutor" and "tiwane" are very important, calling attention to the great amount of observations made in Costa Rica by outsiders.
Analyzing the 25 observers who have the highest number of observations in Costa Rica, only 4 of them have more than 80% of their observations in the country, while 17 have less than 30% of their observations in the country.
In fact, for a country that is not very populous and has significant ecological tourism, the engagement of the population can not be directly related to the proportion of the number of observers in relation to the population of the country. Certainly the density of observations (observations/1,000km²) is also influenced by the presence of outsiders.







Posted on July 8, 2019 02:55 PM by nelson_wisnik nelson_wisnik | 3 comments | Leave a comment

July 5, 2019

Biodiversity in a Calabur tree sapling - update


This is an update of the post on biodiversity observed in a Calabura tree on January 31 this year
https://www.inaturalist.org/journal/nelson_wisnik/21246-biodiversity-in-a-calabur-tree-sapling
Now, six month later, we did other 51 visits to the sapling, which lead to a total of 26 species of insects, remainhing 2 species of arachnids.
New observations has been made, to access them enter the project
https://www.inaturalist.org/projects/observations-of-biodiversity-in-a-calabura-tree
You are welcome.

Posted on July 5, 2019 02:28 PM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment

April 2, 2019

Report of the "April Fool's Day 2019 - BioBlitz"

The project dealt with some species that camouflage themselves in the environ or mimic others as their way to survive, fooling us also.
A simple, basic, statistics, ilustrates how dificult is to observe them.
For birds, Nightjars and Nighthawks, there were only 6 observations including 4 different species. In the same period, there were 10,811 observations of birds of 1,195 different species.
Related to Arachnids, looking for the Cyclosa conica and the Misumena, there were only 5 observations of 2 different species, while, in the same period there were 1,525 observations of arachnids of 295 different species.
Finally, looking for Katydids and Stick insects, one got 101 observations of 28 different species, while, in the same period there were 11,403 observations of 2,846 species of insects.
The species choosed for this project are globaly spread, and the observations came from all the continents (except Antarctic).
They are as fascinate species as difficult to observe them.

https://www.inaturalist.org/projects/april-fool-s-day-2019-bioblitz

Notice: the quantities of observations and species were consulted on April 2nd, 15:55GMT, it is possible to increase as more observations are uploaded, but the dramatic difference must remain.

Posted on April 2, 2019 04:01 PM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment

March 30, 2019

Project "April Fool's Day 2019 - BioBlitz"

Camouflage and mimicry are ways to deceive others. There are numerous species that camouflage or mimic other species to achieve their survival.
We ourselves, observers, are often surprised when we realize what happens during our field endeavors. I mean that so many other situations we do not even realize, we are fooled.
This project pays homage to the species that camouflage and mimic, and challenges us to find them. I selected some species, perhaps more visible, found on almost every continent.
Feel free to join the project and, also, suggest camouflage and mimicry species of your interest. Good luck to all of us!
The distinction between camouflage and mimicry is not always clear when only the model and the mimic are at hand. When the receiver is known and its reactions understood, however, the distinction is quite clear: in mimicry the signals have a special significance for the receiver and for the sender, which has evolved the signals in order to be perceived by the receiver; in camouflage the sender seeks to avoid detection by the receiver through imitation of what is neutral background to the receiver. [1]
In seeking to differentiate between camouflage and mimicry, camouflage can be consider as a more 'passive' attribute, in which an organism has evolved to blend in against a background, whereas mimicry has a more 'active' component to it, whereby an organism copies a specific species or behaviour.[2]

[1] https://www.britannica.com/science/mimicry
[2] https://treesforlife.org.uk/forest/forest-ecology/mimicry/
[3] https://royalsocietypublishing.org/doi/full/10.1098/rspb.2016.2080

Posted on March 30, 2019 03:34 AM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment

March 25, 2019

Project "The World Water Day 2019 - BioBlitz March 22 to 24"

"World Water Day is an annual UN observance day (always on 22 March) that highlights the importance of freshwater. The day is used to advocate for the sustainable management of freshwater resources. World Water Day is celebrated around the world with a variety of events. These can be educational, theatrical, musical or lobbying in nature." [1]
It is well known that the forms of live we deal with in the earth are all, or nearly all, dependent of the water. Being so, we needed to choose some few to catalog in the World Water Day. We avoided the obvious species that expend all their lives in the water (fishes, algae, for exemple), in favor of some that have have relation to water either in time or space, are around us, and do not demand sophisticated equipments to observe them.
"Amphibians are small vertebrates that need water, or a moist environment, to survive.
The species in this group include frogs, toads, salamanders, and newts. All can breathe and absorb water through their very thin skin." [2]
"Most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on earth. Cacti show many adaptations to conserve water." [3]
"Bromeliads often serve as phytotelmata, accumulating water between their leaves. The aquatic habitat created as a result is host to a diverse array of invertebrates, especially aquatic insect larvae. These bromeliad invertebrates benefit their hosts by increasing nitrogen uptake into the plant. [4]
"Nymphaeales, the water lily order of flowering plants, is found in quiet freshwater habitats throughout most of the world.
All plants of the Nymphaeales order are aquatic." [5]
The results show that, for the categories of life being observed by the Project, 62% were observations of Amphibians, while 34% were of Cactuses, only 3% of Bomeliads, and even fewer, only 1% of Nymphaeales.
The result for Nymphaeales did not surprise me, but the result for Amphibians was quite impressive since I hardly observe one.

https://www.inaturalist.org/projects/the-world-water-day-2019-bioblitz-march-22-to-24
https://www.inaturalist.org/projects/the-world-water-day-2019-amphibians-bioblitz
https://www.inaturalist.org/projects/the-world-water-day-2019-cactuses-bioblitz
https://www.inaturalist.org/projects/the-world-water-day-2019-bromeliads-bioblitz
https://www.inaturalist.org/projects/the-world-water-day-2019-nymphaeales-bioblitz

[1] https://en.wikipedia.org/wiki/World_Water_Day
[2] Animal Encyclopedia, National Geographic Book (C) 2012
[3] https://en.wikipedia.org/wiki/Cactus
[4] https://en.wikipedia.org/wiki/Bromeliaceae
[5] https://www.britannica.com/plant/Nymphaeales

Posted on March 25, 2019 10:38 PM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment

February 24, 2019

The Cecropia

Cecropia is an interesting genus, opportunistic in some situations, pioneer in others. This is due to the fact that their seeds germinate and the species develops under sunshine.
When one has new soil, for example a silting of a lake or in the margin of a river, the Cecropia has advantage over other species. This also occurs when a clearing is opened in the woods due to the fall of one or more trees, allowing the insolation to reach the ground. Cecropia survive on poor soils and are part of the early stages of ecological succession.



On the other hand, its life can be short because, providing shade for the growth of other species that do not develop under insolation in the first stage, it is surpassed in height and, consequently, shaded, which causes it to perish. Typically, in the forest, the life of Cecropia lasts for about twelve years.
Many individuals of the genus Cecropia live in symbiosis with ants, which inhabit the hollow of their stems and, in turn, protect them from insects that try to feed on their leaves.
Moreover, the fruits of Cecropia are appreciated by several species of birds, and its leaves are part of the menu of the sloth and the howler monkey.



To access the observations, "explore" filtering for the person's name "nelson_wisnik" and the Description/tags "Cecropia". You are welcome.

Posted on February 24, 2019 01:35 AM by nelson_wisnik nelson_wisnik | 0 comments | Leave a comment