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Carnivorous plants are green plants, often growing on soils that are low on nutrients. The plants produce Carbohydrates by photosynthesis jsut like normal plants but to obtain Nitrogen, Phosphorous and spore elements they catch living prey.
But if you think that they are all veracious green monsters that devour everything that comes in their way, you are wrong!
Yes they usually do catch and digest often insects, other arthropods and even occasionally vertebrates. A recent discovery for instance show that in Canada young salamanders fall prey to pitcher plants (Sarracenia purpurea). And personally I have been witness of  the discovery of the remains of a shrew  in a pitcher of Nepenthes attenboroughi on the Phillipines. However these two examples are just exceptions to the rule.

Vegetarian carnivores

Some carnivorous plants have even a (partially) vegetarian diet:
at least some of the aquatic bladderworts (Utricularia sp.) have algae and pollen as an important food source. This is in addition to small aquatic organism like waterfleas (Daphnia spp).
Another “vegetarian” is Nepenthes ampullaria. N. ampullaria can be considered to be detritivore living on leaves, The plant produces groups of lidless pitchers in the undergrowth of rainforests, often near ferns. The (fern)leaves are caught by the plant. Digestion takes place with the help of a small ecosystem present in the water filled pitchers. This include bacteria, mosquito larvae, other aquatic insect larvae and sometimes even crabs or frogs. The infauna of the pitchers helps the plant with the uptake the nutrients from the leaves.

Nepenthes bicalcarata is a species of pitcher plant with, like a contradiction in termini, a special relation with insects. It is often home to a species of ant that nest in the hollow tendrils of the plant. The ants (Camponotus schmitzii) act as a body guard: the remove weeds and pests from the plant. Amazingly the ants are able to dive into the pitcher fluid to feed on prey. As a result the nutrients from the prey can be used more efficiently by the plant.

Alternative food sources

Some Nepenthes species have an alternative source for their nitrogen and spore elements. A few species have a mutualistic relationship with mammals. Nepenthes hemlesyana from Borneo, is home small bats (Kerivoula hardwickii) see https://www.nature.com/articles/s41598-017-13535-5. The bats find a safe shelter in the adapted pitchers during daytime. In return the plant makes profit from the bat’s droppings that are a food source for the plant. Besides in N. hemlesyana these bats occasionally also roost in the closely related, but non specialized, pitchers of N. rafflesiana.

In the Bornean highlands some of the larger Nepenthes species act like a toilet: N. rajah, N. lowii and N. macrophylla secrete carbohydrates from their lids. This is a treat for the mountain tree shrew (Tupaia montanus) and the summit rat (Rattus baluensis). As they feed on the exudate, they often defecate. Just like N. hemlesyana the pitcher plants take up the nutrients from the scat. A few other Nepenthes species, e.g. N. jamban, resemble toilets, but whether they also collect scat is unknown.

 

One of the largest mysteries from nature is the origin of the Borneo elephant.
The North Eastern part of the island of Borneo is home to a small population of the Asian elephant (Elephas maximus). The Borneo elephant  (Elephas maximus borneensis) is one of the four recognized subspecies of the Asian elephant. In fact these elephants are slightly smaller than the elephants from the Asian continent and hence the nick name pygmy elephant. The population contains only about 1500 animals, living in the Malaysian state of Sabah and occasionally at the other side of the border in East Kalimantan, Indonesia. The elephants of Borneo are about 30% smaller than their cousins.

The question that raised by many people is where do these elephants come from? Due to their limited distribution and the absence of fossils it was once thought that these animals were introduced by men. One theory is that the elephants arrived at Borneo as a gift for the local sultan in the 17^th century. While the other theory favours a natural origin of the Bornean elephants.

Recently I found an article about the genetics about the Borneo elepant. It revealed that the pygmy elephant is genetically different from the Asian elephant on the mainland.
It also revealed that the genetic diversity within the population of pygmy is quite high. This excludes the possibility that these elephants are all descendants of a small group of elephants. Most likely they arrived on Borneo via a land bridge probably 11000 – 18000 years ago. But whether they arrived from Java or from the mainland of Asia is not clear. What I understood is that it is still unclear why they only live in North East Borneo, far from the possible land bridge(s).

Close encounter with the pygmy elephant

In 2016 I made a very nice trio through several natural reserves of Malaysian parts of Borneo.  The famous Kinabantangan river  was part of the trip. This is the second largest river of the island and flows in the North East of the island. Along the river many I spotted many wild animals, including proboscis monkeys, bearded pigs and orangutans. I will tell more about them in a future episode.
At the second day of our stay at the river lodge, guides told us that some elephants were spotted upstream. The other day we departed from the lodge in two smaller boats for our search for the elephants. It took a few hours before the trackers found tracks of these animals. We continued searching somewhat downstream again and yes there they were!

We saw a small family group of at least seven including a playful calf was fouraging on the riverbank. It was really fun to watch them and amazing to see the these giant pygmies disappearing in to the forest in the blink of an eye. It was still not over with our luck, when we were on the way back to the lodge we also found an elephant bull in the water. So with a good feeling I good say goodbye to the river.

Drosera aff. eremaea is after D. ramellosa and D. macrantha, the next species to be introduced to you. The aff. stands for species affinis. This means that the species has an affinity to, but is not identical to the species named. In this case I will show you a sundew that is, most likely, closely related to Drosera eremaea, though it is clearly different from the “true” D. eremaea.
Drosera eremaea is a tuberous sundew species related to D. macrantha and it has been considered as a subspecies of it. It’s habitat is formed by semi-arid areas (eremea is the Greek word for desert) in Western Australia with hot summers.

Drosera eremaea is a plant that is apparently not very common in cultivation. There seem to be some variability in this species. The typical from is an erect, usually pale green species, about 20 cm high with white or pink flowers. But there are also forms getting much taller than this:40 or even 60 cm.
This species can easily be recognized by the “pseudo rosette”. Grouped leaves can be found at the base of the stem with broadly elliptic, almost reniform leaves. Drosera eremae reproduces asexually by producing daughter tubers via adventitious stolons.

Drosera aff. eremaea in my collection

Well, so far the theory, let’s have a closer look at my plant. I obtained it about 2009, so this is one of the tuberous sundew species that I grow for the longest period over now. The plant, from Darren ‘Spot’ Cullen in Tasmania, is obviously different from the typical Drosera eremaea so therefore I consider it as D. aff eremaea. Unfortunately Darren does not know the origin of the plant. Like D. eremaea my D. aff. eremaea is pale green and forms a kind of a pseudo rosette and the entire stem is covered with minute glands. But in many other aspects it clearly differs from the typical form. Drosera aff. eremaea is a scrambling plant about 50 – 60 cm tall and in all these years I have not seen any adventitious stolon formation at all.
The odd thing about the D. aff eremaea that I grow, is the formation of additional leaves in many nodes. Where other erect or climbing species produce sets of 1 – 3 leaves in a node, my plant often, especially in the lower part of the stem, my plants produce more. One extra set of three leaves (making it 5 or 6) or even 2 extra sets of leaves (making it up to 8 leaves in a node) are quite often produced. Occasionally also small branches are produced.
Another diagnostic feature is the presence of tiny glands at the back side of some of the leaves especially closer to the top. This plant is one of the first tubers to awake in the season (after D. macrantha “rock outcrop form”) but is also the first on to die back.

It took a few years, but since I switched from T5 tubes to LED lights, I got the growing conditions right for this odd plant. Now I got it flowering for the second year in succession. The flowers are whitish with a faint pink coloration and about 3 cm in diameter.

Another reaction of the plant is that it now produces daughter tubers, subterranean and not via stolons.
Now I have ordered another D. (aff) eremaea from Allen Lowrie (a dark pink, 60 cm tall form), I am curious how different or similar this plant will be from the one I grow. Perhaps I can get my hands at another D. eremaea plant next summer.

In this blog I will tell you somehting about Drosera macrantha, one of the tallest species in my collection. After my first blog about Drosera ramellosa, I will write again something about one of the sundews from my collection.  D. macrantha (also known as the bridal Rainbow) is, like D. ramellosa,  a tuberous sundew from South West Australia. Where D. ramellosa is relatively small (max 15 cm), Drosera macrantha is a climbing/scrambling species that can get 50 -150 cm tall. This makes is one of the tallest species of the genus. It does not make a rosette.

The stem is covered with alternating groups of three cupped shaped leaves. The leaves might be green but are also often red coloured. Drosera macrantha might be one of the tallest species of the genus, but the leaves are only 2.5 – 5 mm wide. With the central petiole significantly longer than the other two leaves. This leave is often used to anchor the plant to shrubs or rocks to direct the flowers into the open. It eventually give rise to between 5 and 20 white flowers at the top of the stem. The flowers, like in many sundews, are only open for one day. Except for the lower part of the stem is covered with hair like (often red coloured) glands.

 

 

 

 

 

 

 

Like most of the tuberous sundews, D. macrantha is limited to South West Australia where it is widespread. It is a variable. species. Actually D. macrantha should be considered as a member from a species complex. In the recent past some varieties and subspecies have been elevated to the species level and it is well possible that more will follow.
There are large differences in size between different varieties and there is even one that makes a kind of basic rosette.

Drosera macrantha in my collection

At the moment I do have three different clones growing in my collection. It is easy to see the variability in the species even from this small sample size.
One plant was originally collected near the village of Carbarup in West Australia is initially growing erect, leaning over when it gets taller. Related to this issue are the relatively short (central)petioles, these become only elongated near the top. This plant will reach a length of about 50 cm. The leaves are quite large, deeply cupped and slightly wrinkled. This plant will only occasionally produce daughter tubers.

 

 

 

 

 

 

 

 

On the other hand I do have two different “rock outcrop” forms. These are slender, have smaller, shallower leaves, but one of them makes it to at least 80 cm tall. The rock outcrop plants produce daughter tubers easily. The second rock outcrop form is really fine, but somehow did not flower yet.

 

I have visited Keoladeo National park (formerly Bharatpur Bird sanctuary), in the north of India in Bharatpur, Rajastan some years ago.
The visit was part of a two weeks trip through India, that included also the visit of two other NP’s and some monuments like the Taj Mahal and the red fortress of Agra.
The park is a man- made wetland, for years it has been the private hunting ground for the local maharaja, but now it is a famous natural reserve, world famous for its birdlife (366 species!!!) and therefore recognized as a world heritage site.

I entered the reserve with a rickshaw, though this means of transport can only be used for the main entrance road. Other parts of the reserve are easily accessible on foot. There are no virtually no height differences and no dangerous animals.

As I  mentioned before, the park is rich in birds, especially water loving birds like herons, storks, egrets, cormorants and ducks. Close to the entrance several trees were filled with nests of painted storks (Mycteria leucocephala) accompanied by little cormorants (Microcarbo niger) and little egrets (Egretta garzetta). Other birds present were peacocks, bee-eaters, kingfishers and various birds of prey.

Besides of the birds you can see also reptiles like monitor lizards and pythons. Unfortunately I did not see any pythons during my visit. But based on the number of burrows I have seen, Keoladeo NP is home to a healthy population of these large snakes.

 

As soon as I entered the park I spotted a rhesus macaque (Macaca mulatta) and further more nilgais (Boselaphus tragocamelus), Asia’s largest antelope could easily be seen. The nilgai or blue bull can exclusively found at in Indian subcontinent.  You can find them in large parts of India and just over the borders with Nepal and Pakistan. The males have a shoulder height of approximately 1.50 meter and weigh about 240 kilograms.

Some Utricularia

For some reason I did not expect to see carnivorous plants, but it turned that I was wrong!
Quite soon after arrival I found a pond with yellow flowering plants in the water, unmistakable a bladderworth. These yellow flowers belonged to Utricularia aurea (“golden bladderwoth”). It is one of the most common aquatic bladderworths in tropical Asia. You can easily identified this species by the long seed capsules.
On my second in the park there was another surprise, I stumbled on many white flowering plants in the water. The flower scape was supported by a kind a raft formed by a whorl of cigar shaped floats. This bladderworth was later identified as Utricularia stellaris (“star shaped bladderworth”).

The identification of this species was not easy. This species usually has yellow flowers though in some populations they have white flowers with violet nerves.
U. stellaris is closely related to U. inflexa (a white flowered species). These two species have been considered as one single species in the past. The plants that I have observed in Keoladeo NP seem to represent some kind of intermediate between this species (not really uncommon).

 

 

 

 

 

 

 

 

The plants that I observed in this park grew much more vigorous than  mentioned in literature. Peter Taylor has mentioned in his monograph on Utricularia a maximum number of 12 flowers for U. stellaris. Quite remarkable is that the  plants that I did observe had up to at least 23 flowers and also had more floats than stated in literature. Utricularia stellaris is widespread in Africa and has a patchy distribution from Asia to North Australia.

Last November I went with two friends for a long weekend to the island of Terschelling.
It is one of the “waddeneilanden”, a chain of smaller and somewhat larger islands stretching from the North West from the Netherlands till the South west of Denmark.

With 674 km2 Terschelling is not a really large island. It is known for its cranberries, the story goes that some barrels washed ashore in the 19^th century and the finder moved it in to the dunes because he thought that there might be some alcoholic beverage inside.
We went there to run a half marathon (I finished in 1:32:47 a personal best). Before and after that we had time to explore the dunes and beach.
Sometimes, like two years ago, you can see some seals and if you are lucky, even a porpoise.
Not this time though.

After a nice hike through the dunes we reached to the North sea beach. At first we spotted a few starfish stranded at the beach. Later on my attention was drawn by large numbers of gulls diving into the surf. The group consisted mainly out of European herring gulls (Larus argentatus) together with some great black-backed gulls (Larus marinus, world’s largest gull), two quite common species in this time of the year.
So I decided to close in a bit a see what the attraction could be.

Soon enough I spotted a herring gull bringing something on land. Somewhat surprising there it turned that there was starfish on the menu! I have identified them as common starfish (Asterias rubens), species common along the shores of the Northern hemisphere.
Some of the gulls got company of a few sanderlings (Calidiris alba), apparently hoping for some scraps.

Sanderlings

Sanderlings are a common sight along the beaches in winter. These funny little birds follow the waves up and down when they reach the beach. They breed in the arctic like Canada, Greenland and Siberia. I noted that a few of them had some coloured rings at both legs. These rings make them easy to identify so more info about their survival, migration strategies, timing of the migration and the general behaviour of the species. This is a project of the Groningen university. In case you see one bird with colour rings you can enter the information at www.animaltrack.org. At this website it is possible to see the history of the bird. The two birds with coloured rings have been ringed close by Terschelling and so far only been seen on the shores of the Island.

Pinguicula (butterworth) is a fairly large genus of Carnivorous plants related to both Utricularia and Genlisea. Worldwide there are about 100 butterworth species. They can be found in (cold temperate) Eurasia and on the western hemisphere. There is only one species of Pinguicula native in the Netherlands: P. vulgaris (the common butterworth). It is the most widespread species from the genus. It can be found virtually in all cold temperate regions of the Northern Hemisphere, including the Netherlands.

In the Netherlands P. vulgaris is the only butterworth species that is native. It is nowadays a very rare plant with its distribution, mainly, limited to a few areas in the east, close to the German border. One remark about the distribution in the Netherlands, the historical distribution of the species has been limited roughly to the centre of the country eastwards. This distribution pattern is due to the soil composition. In the west the soils are mainly peat or clay based, while in the east  often sandy soils are found.

It prefers open, sunny, spaces like nutrient deficient meadows and sphagnum bogs. P. vulgaris can often be found together with some sundews (Drosera intermedia and D. rotundifolia).
The P. vulgaris population crashed at around 1900. This probably due the extension of agriculture which led dehydration and nitrification of the habitat. The decrease continued during the 20^th century. Nowadays most populations are well protected and there are a few new populations, but whether this means that the decrease of this species has stopped? I am not sure about that.

But luckily there are still a few places where this species can be admired. Some of the populations are really small, with only a few plants. However there are at least two species where, if you are lucky, you can see a blue hazw in the meadow, caused by the flowers  (see above). Besides the blue/purple flowers the plants can be spotted relatively easily by its yellows leaves, forming a rosette. As might be suspected, this species can resist frost. In wintertime the plant retreats to a winterbud (“hibernaculum”).

Cultivation of Pinguicula vulgaris

Unfortunately I am not longer growing this nice species. I have tried it a few times, but not with to much success. This in contrary to a few other hardy Pinguicula species like P. grandiflora and P. macroceras. One of the thing that might be the problem is that the plants do not get enough sunlight, especially at the end of the summer. So I have to cut some trees this winter….

The species can be grown in a regular mix of peat and sand. It can be best grown outside on a sunny place. It should be exposed to a cold period in wintertime. The drainage, especially in wintertime should be good, to prevent rot.

Pinguicula vulgaris can be propagated from seed, but even more easily from gemmae. As mentioned before, in wintertime the plant form a winterbud. And attached to this are smaller buds (gemmae). These can easily be taken of the mother plant and will grow to a new plant. In nature these gemmae are washed away and spread by the rain.