Important observations in the Paraguayan forests.

By Hans, Baron Berlepsch. Published in 1917 in the Journal für Ornithologie and translated by the website editor.

(Website editor: Hans, Baron Berlepsch, nicknamed Vogel-Hans (Hans the Birdman), was born in 1857 and died in 1933. He made his journey to South America in 1886 when he was 29 years old. He was a pioneer in bird conservation and was one of the first to express the idea that the other creatures, which populate our planet, have as much right to exist as human beings. This was very unusual at the height of the industrial revolution in Europe and elsewhere. When not travelling he lived on the family estate in Thuringia, eastern Germany, where he developed, encouraged and proselytised the practice of bird conservation. He also kept a flock of Carolina Parakeets (Conuropsis carolinensis) at liberty there. 

Below is a translation of a short article he published in 1917, which was based on his diaries of his journey. The text was sometimes not easy to translate as he wrote in a quite difficult style. Website visitors, who can read German, can view the original text by clicking here. My main interest was his mention of seeing Anodorhynchus leari, which is plainly impossible. I believe he may have seen Glaucous Macaws (Anodorhynchus glaucus). We have managed to get a map of his journey and that shows he travelled from Asunción, the capital of Paraguay, across southeast Paraguay to the River Paraná, then through the adjoining south-western areas of Brazil before heading north through Brazil. He therefore travelled not far from the nesting sites for the Glaucous Macaw reported by D'Orbigny and visited and reported on by me in 1992.)      ___________________________________________________________________________________________

In 1886 I travelled for eight months – from February to October in South America. This journey was a long time in the making. As a schoolboy I thought about travelling into completely unknown territory. I got to know Dr. Von den Steinen after his research trip on the upper reaches of the Xingú and decided to go further south through the still unknown eastern parts of Paraguay and beyond to the western parts of the adjoining southern provinces of Brazil. I had intended to make a detour on my way home through the estuary of the Amazon River, but had to give this up as the journey through the surrounding forest would take more than three months instead of the four to five weeks originally considered necessary.

As final preparation for this journey I learnt Spanish, practiced anew rapid specimen production and studied the zoological works of Burmeister, in particular those devoted to ornithology. I took these in my limited amount of baggage and Professor Burmeister was kind enough to give me some thorough instruction personally in Buenos Aires. Fortunately at the last moment I managed to recruit Captain Geisel as travel companion.  It was more common interest than friendship which brought us together and we were able to put together our modest knowledge to our advantage. Geisel was a passionate botanist and a really good anthropologist. He loyally shared the often not inconsiderable travails and dangers.

This journey was dedicated mainly to ornithological studies and in these tropical and subtropical regions I made new and interesting discoveries at every step. I do not have the time here for a general description of the journey or even for a comprehensive account of crossing the forest. This would in any case go far beyond the limited goals for this work.  I will therefore only speak from a certain standpoint and as a result only briefly mention that which had a fruitful and elucidating effect on my ornithological and especially my later bird conservation activities. These were mainly three observations.

Before I left the forest again it was late autumn and winter – May, June, July.  Despite this every evening enormous flocks of Amazon parrots  - Amazona festiva L.  and Amazona dufresnei  Sw., - as well as smaller groups of the three macaw species present there -Ara chloropterus GRAY, Ara ararauna L. and Anodorhynchus leari Bp. flew to their breeding places and spent the night in their old nesting cavities.  Detailed observations shortly before nightfall as it gradually becomes dark are known not to exist at this latitude and in the early morning I discovered that not one or two, but often four to five birds occupied one cavity. (Website Ed:  Berlepsch must have incorrectly identified the parrot species because A. festiva and A. dufresnei do not occur anywhere near Paraguay and Anodorhynchus leari is certainly not found there. I believe that if he saw blue macaws in Paraguay it could only have been glaucus. More on this later)

This observation encouraged the thought that perhaps it was the same at our latitude. My later observations have confirmed this. Here in our country, therefore certainly all over the world, all cavity breeders, at least if they are native birds, return to the nesting cavities every evening even outside the breeding period. The exceptions appear to be those like starlings in very large flocks which seek shelter in reeds, ivy and similar vegetation. Here at our latitude they can also find protection against the cold. Often several birds roost together in one cavity as they did there.  At the beginning of winter before the struggle for existence thins their ranks the cavities will be often really stuffed with birds. Just in one little titmouse cavity up to nine titmice, three great tits and six marsh tits have been found. 

This discovery has brought about a change in the field of bird conservation, which one cannot estimate high enough. Nest-boxes were often removed after the breeding period to preserve them longer and installed again the following year after the arrival of good weather. I recall how speculative nest-box manufacturers sought to commend their products by constructing their nest-boxes in such a way to make this easier. 

Now we know that the cavity breeders need their cavities in winter just as much as in the breeding period and this method of preservation actually resulted in a systematic destruction of the birds.

The second observation of the journey has been to the benefit of the nest-builders. The measures we now adopt so successfully for their protection are a direct result of that journey. They are based on detailed observation of the nesting sites selected in the still untouched virgin wild.
The deep dark jungle is dead just like the forest interior here. Yes, it may sound unbelievable, but in my diary I noted seven consecutive days when I neither saw nor heard a living creature, including amphibians and snakes. The damp, fever-laden atmosphere will sooner or later kill every higher living being. Only certain insect species live there and they were an absolute pain to us during those days. The forest life of our imaginations occurs only on the edges of the forest, along water courses and other open areas.  

Birdlife is especially rich here. It’s where we encountered all sorts of song, marsh, climbing and predatory birds - all together.  It’s where thousands of the afore-mentioned parrot species appeared reminding me of our winter flocks of crows. They could be heard when they were still several kilometres away. It’s where lazy vultures perch and agile falcons fly.  It’s where a curious yellow thing hopped around like a long cucumber in the gloom of the tree-top until we realised it was only the bill of a toucan. Enormous numbers of small insect-feeders fly about the hollow trees or other especially rich feeding sources and are taken in large numbers by the raptors assembled there. The latter are unconcerned and blameless. The human eye has not seen anything here yet that is either useful or harmful as far as a bird is concerned. (Website editor: the last two sentences in the German text were at first puzzling, but then I realized he was referring to moral concerns, which birds, of course, do not have. I have therefore tweaked the text a little to try to make this clearer.) 

This territory was then also a gold-mine for observations and it was here too where I discovered in the undergrowth, which was mainly a thorn species with long needles, innumerable nests.

It was very noticeable that the density of the nests was very variable even though the vegetation was very similar in type and quantity as well as in the amount of shadow it enjoyed. In some places the nests were almost non-existent, whereas elsewhere they were so dense that the undergrowth appeared to be covered with a thick moss. I found the explanation for this after continued observation.

The bushes were the most desirable locations to nest, apart from the rampant creepers, for the following reason. In the moist climate of the forest growth and decay follow one another very quickly. Often the tree trunks have decayed below whilst above masses of branches and stumps of wood still hang in the creepers. Through wind, bird movements and other causes these pieces then gradually fall down – incidentally not entirely without danger to ourselves, my companion, Geisel, escaped death on one occasion – and break though the bushes below. The dormant seeds germinate in these broken areas and develop into new growth and the innumerable nests are located on top of this.     

I saw therefore that it depended less on the position and type of vegetation, but far more on its condition. The more deformed it was because of the afore-mentioned circumstances the more nests were located there.

Now I also remembered that I experienced something similar on a journey in Africa on the southern slopes of the Atlas Mountains. At the time, however, I did not think anything further about it.

It is due to these perceptions that the bird conservation woodland now existing here has its origin. I try in a relatively short period of time to reproduce artificially the same effect, which I found had existed there for eons by itself.

Under bird conservation woodland is now understood the planting of certain tree species where after the appropriate care and especially cutting, the same excellent nesting opportunities are achieved as those which occurred in the forest then and are still to be found there now.

A third observation led me to the fundamentals of winter feeding. This was those afore-mentioned hollow trees, often of enormous dimensions, as well as other more or less sheltered feeding sources. The latter consisted of tree stumps or fallen tree tops overgrown with tangled masses of creepers, moss, ferns etc. In the decaying and decomposed walls of this growth the birds find a perpetual menu and what is probably most important of all more or less weather-proof refuge.                                                         

That is admittedly of far less importance there, but it was different when such growth was to be found here. The memory of those larders in the forest later led to the idea to re-create something like it here and taught me the most important condition for all winter feeding – protection against the elements.

These are the observations from that journey, which I wanted to share, and I am sure readers will concur that they have been highly fruitful and elucidating. As far as conservation of birds is concerned they are certainly the most important sections I have read in the book of nature.

End of article.

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 " Naturam expellas furca, tamen usque recurret "

( If you drive out nature with a pitchfork, she will soon find a way back)

Horace (65-8 BC)