Poor Goshawk Breeding Success in Berlin Jul 10, 2014
2014 was not a good breeding season for Berlin's goshawk population. For unknown reasons, many pairs did not breed and others had little success, raising one or two instead of three or four hatchlings. Moreover, in many well-known breeding pairs, one of the adult and experienced partners was replaced by a young (2nd year) bird which bred for the first time. Why are so many adult goshawks missing? Is this a hint to human persecution? For the moment, we don't know. However, the goshawk pair in my neighborhood was successful, raising two hatchlings as usual.
The pictures above show the two siblings waiting to be fed by their parents, and one of the birds stretching. In the lowermost picture, the color band of the actual banding programme is visible.
The Apical Region of the Mediterranean Heart-Urchin Echinocardium fenauxi Pequignat, 1963Jun 26, 2014
This is a close-up view (1x2 mm) of the apical region of the heart urchin Echinocardium fenauxi, a sea urchin of the order Spatangoida. This species is to be found in parts of the Mediterranean, where it is endemic. Prior to photography, the test has been denuded from spines and cleaned with hydrogen peroxide to reveal the delicate surface details. In the center of the image, the apical disk with the madreporite (sieve plate) and the four genital pores are visible. Above, two straight rows of ambulacral pores belonging to the frontal ambulacrum reach for the margin of the frame. Here, and in contrast to the otherwise similar and much commoner species Echinocardium cordatum, the pores are arranged in regular lines, whereas in the latter species, the pores are alternating in an irregular manner. The ambulacral rows of pores are guarded by enlarged tubercles which supported specialized spines. Since E. fenauxi is a species burrowing deep into fine to medium sandy substrates, the spines had the function of forming a protective arc over the ambulacral furrow to prevent sand grains blocking the respiratory tube feet and the ciliated mucus band transporting nutrients to the mouth. The apical disk and the frontal ambulacrum are bounded by a fasciole. In the case of this species it is an internal fasciole, a diagnostic feature of the Echinocardiid family. Fascioles are bands of milliary ciliated spines creating water currents for the animal’s respiration and waste disposal. In the lower corners of the image, parts of the paired ambulacra with their large respiratory pores can be seen.
This picture is an excellent example that high quality imaging complying with scientific standards can be carried out with low-budget equipment. This photograph has been taken with my Nikon Coolpix 4500 workhorse and a mounted Nikon SL-1 ring light. This old-time 4mp compact digicam went on sale in July 2002 and is still available from Ebay. Its excellent depth of field and close-up proficiencies still make it my first choice for scientific imaging.
A Black-Browed Albatross at HeligolandJun 06, 2014
The Black-browed Albatross (Thalassarche melanophris) is a pelagic bird of the southern oceans which breeds on the subantarctic islands between South America to New Zealand. Its normal northern range is in the Humboldt Current to Peru and in the Atlantic to southern Brazil. Occasionally birds show up in the northern hemisphere. So did an adult Black-browed Albatross which was first noticed at Skagen (Denmark) on the morning of May 27th. Later that day the bird was seen from a vessel off the Swedish coast. On next morning (cloudy and windy) the bird was first seen on the roadstead between Heligoland main island and the Heligoland dune, heading north. It came around briefly later that day and the next morning, only seen by few excited birders. Later on May 29th, the sky had cleared and the wind declined, the bird pleased numerous birders gathering at the “Lange Anna” (a famous sandstone pinnacle), by flying several circuits just over their heads, before it flew off and was not seen any more for the next couple of days. It returned to the island on June 4th and was also seen the following day.
There are about 30 records in Western Europe including birds building nests in Northern Gannet colonies and returning for many years. According to Howell (2012), summer records on the northern Hemisphere mirror the species’ higher-latitude summer distribution and lower-latitude winter distribution in the southern hemisphere. This is the first species record for Heligoland and the second for Germany.
Note: Heligoland is a small German archipelago in the North Sea, located 46 kilometers off the German coastline. It consists of two islands: The main island and the “dune”. What Cape May is for American birders and the Isles of Scilly for the British, is Heligoland for the German Birding community.
Start of the thunderstorm seasonApr 23, 2014
In the northeast part of Germany, the thunderstorm season traditionally starts in the last decade of April. Punctually, the first severe T-storms appeared in the afternoon of April 22. Responsible for this development is a cut-off low with very cold temperatures in the upper level and a warm and moist air mass of Mediterranean origin in the low level flowing in from the southeast. Diurnal heating and a number of convergences (outflow-generated or synoptic) triggered thunderstorm activities in the late afternoon which occasionally became multi cell clusters with linear appearance. The slow moving systems caused high precip locally whereas Berlin remained bone dry. There will not be much change of the general synoptic situation until Sunday leaving us confident for a good start of this year’s t-storm season. The image above shows one of the closer cells at the eastern margin of Berlin.
Mating GoshawksMar 21, 2014
After some hard- and software problems (solved), I loaded up a number of goshawk images of this years‘ courtship/breeding season. Among these is a sequence of a mating goshawk pair. Three images are shown here. The female is a second year immature, breeding for the first time in her life. The male is adult, but suffers from a lesion of the left eye. The complete sequence and many more new images can be viewed in the Birds of Prey gallery.
Tracks and Signs: Kingfisher PelletsFeb 28, 2014
As many other birds do, kingfishers (Alcedo atthis) regurgitate pellets consisting of indigestible remains of their diet. Since kingfishers are specialized fish predators, these remains consist of fish bones and scales. Surprisingly, no figures are available from literature, at least not from popular field guides such as Mark Elbroch’ s amazing “Bird Tracks and Signs” and Preben Bang’s “Animal Tracks and Signs”.
So now, here it is: Underneath a favored kingfisher perch I found an accumulation of numerous pellets of different ages. They are elongate, cylindrical with rounded, blunt rather than pointed ends. They measure approximately 20 mm in length and are up to 10 mm thick. The colour is whitish. Since the pellets are not covered with mucus, they decay rapidly, as illustrated by the third image of an aged pellet.
This is the first contribution of a series dedicated to animal tracks and signs
Shooting the CurlJan 23, 2014
I love waves. The raw power and pure energy fascinates me. I can spend hours and hours watching a big swell approaching the shore, generated and driven by storms somewhere out in the open ocean. Early morning or evening light and a fresh offshore breeze blowing the spray over the wave crests generate stark images of nature’s powerful beauty. The west coast of Fuerteventura (Canary Islands) is a wonderful and easy-to-reach place for wave-watchers. You have miles of untouched rugged coastlines, crystal-clear water and often a big swell with a wonderful shorebreak (at least during the winter months). Furthermore, the reliable trade winds blowing from the northeast cause a steep and spectacularly breaking surf. For photography, I mostly used my EOS 7D together with the EF 70-200 mm f/2.8 II and EF 400 mm f/5.6 lenses. Selecting Tv mode with a fast shutter speed (1/2500s), AF on “Ai” plus zonal mode and high speed continuous shooting proved to be the best setting.
Capturing Swifts in Flight – More than Spray and Pray!Jan 10, 2014
Photographing birds in flight is not an easy task. Capturing swifts in flight is a challenge! Swifts are considerably small birds, their flight is erratic and flight speed is incredibly fast. When hunting insects or during courtship display, swifts can reach maximum speeds of 200 km/h (125 mph)! However, achieving sharp images of flying swifts is more than spray and pray. You can increase your chances of success when you are prepared and keep some important things in mind. Here is a short tutorial of how to capture tack sharp images of flying swifts. Of course, it can be applied for other fast flying birds as well.
Locality and lighting: First, you need to find a suitable locality where swifts are commonly passing by. This could be in the vicinity of a breeding colony or at preferred hunting sites. These may be found far away from their breeding places. Since you want the swifts to pass by at eye level, it would be favorable to position yourself on a raised structure. The roof of a large building or a cliff edge will work well. Also keep in mind that during cold or windy weather, swifts prefer to hunt over open water such as lakes and ponds. You also don’t want the swift to occur as a black silhouette against the sky, so lighting is very important. Avoid overcast skies when the birds will appear against a white background. The best light is front lighting. Shooting against the western sky in the morning and against the eastern sky in the evening will work fine. At my experience the best light occurs about one hour after sunrise and one hour before sunset, respectively, when it is bright enough to achieve high shutter speeds. Avoid the dull and harsh light of midday.
Lens and camera choice: Swifts are small birds, about the equal size of a sparrow, so a long lens is a must. I tested the Canon EF 70-200mm /f2.8 L USM II (with and without the 1.4 x extender), the EF 300mm /f2.8 L USM and the EF 400mm /f5.6 L. The 70-200mm lens does not match the focal length you will need and the 300mm /f2.8 is a heavy weight. You need to shoot free-handed over a considerable time span and this lens will soon lead to muscle fatigue (unless you are not a trained U.S marine!). So the light-weight and handy EF 400mm /f5.6 lens is my favorite choice. Your camera body should possess a good and fast autofocus, a high burst rate (about 8fps or more) and a sufficient ISO/noise performance. I am mostly shooting with Canon’s EOS 7D which is an sufficient camera for this purpose. Moreover, its sensor–related cropping factor adds a subjective 1.6x of focal length.
Camera settings: High shutter speed is the name of the game. Everything faster than 1/1600s will do, but I prefer higher shutter speeds such as 1/2500s. Set your camera on Tv mode and select shutter speed. If you start shooting after sunrise, subsequently adjust shutter speed when daylight continues to improve. Select ISO “auto”. Shooting against a bright sky requires exposure compensation of + 1 to 1 ½ f-stops. If your lens or camera possesses an image stabilizer (IS), deactivate it. At the applied shutter speeds IS is not only unnecessary but moreover, the engine processing time makes your camera slower. Set your camera’s shooting mode on “High speed continuous shooting”. Make sure that you have installed the camera’s newest firmware. For example, in the Canon EOS 7D, updating the firmware almost duplicated the camera’s image buffer when shooting at the maximum 8fps, letting you to grab up to 25 RAW images (15 with the 1.0 firmware) before things start to slow down. Select Autofocus mode “AI Servo AF”. Generally I prefer single point AF with the central AF point active. This is the most accurate and fastest AF point available. However, you will see that it is nearly impossible to keep a small and fast flying bird in the center of the viewfinder which furthermore makes unpredictable turns and maneuvers. I therefore achieved much better results selecting “Zone AF” with the central zone activated. This allows 11 sensors (in the EOS 7D) to keep the subject in focus. It is also very useful to set custom function “AI Servo tracking sensitivity” to “Slow”. This keeps the camera from jumping quickly to the background if the sensor falls off the subject momentarily. In my EOS 7D, this is custom function C.Fn III/1. Check out your camera instructions for other cameras/brands.
Shooting strategy: When you are on location with your camera prepared, make sure that the battery is charged (with a second one in your bag) and that you've got enough memory space in your camera (the last point mentioned is not negelectable since shooting numerous bursts will fill up your memory card much faster than you may think!). So you are ready to shoot. Swifts have their activity maximum in the morning hours and in the late afternoon until dawn. These are also the times when they tend to fly low. During the rest of the day, they are hunting actively as well but do so at much higher altitudes. Once you have spotted a flock of swifts or a single bird flying into your direction, select one of them in the viewfinder and try to keep it in the center. It is also important to pre-focus on distant birds. Press the AF button when the bird approaches and track the bird until it is in shooting distance. Shoot a burst while panning the camera. You need to react fast and response quickly. This is a little bit like skeet shooting and a large part of the fun! Do not try to switch to another bird when you lost your target in the viewfinder. Wait for another flock. The rest is practice. I still discard 98 percent of the images, but 2 percent are keepers.
In central Europe, swifts are elusive summer birds arriving in May and leaving in August, so be prepared.
Berlin: Goshawk Capital of the WorldDec 04, 2013
The Goshawk (Accipiter gentilis
) is a magnificent and powerful raptor distributed all over the Palaearctic and parts of North America. Hated and illegally pursued by pigeon breeders and gamekeepers, it remains a timid woodland bird over large parts of its range. Not so in Berlin! The buzzy German capital with its vivid night life, club scene and cultural offerings not only attracts flocks of tourists but also hosts a large and healthy population of the Northern goshawk. Since monitoring started in the 1980s, the population number is constantly growing up to recent > 85 breeding pairs with an estimated number of unknown pairs in Berlin’s large forests. In Berlin, goshawks prefer to breed in parks and cemeteries where they build their large nests in the tops of old trees. Courtship begins in January when the mating calls can be noticed by the wary observer. Egg deposition is generally in March. One to four hatchlings are raised which become full-fledged in July. Berlin’s goshawks mainly feed on domestic pigeons and rats, thus rendering a great job to control these pests.
To learn more about origin, dispersal, longevity and population dynamics of Berlin’s goshawks, a color banding program has been started in 2012. Detailed information (in German) can be found here
Urbanisation of goshawks has occurred also in other large European cities such as Amsterdam, Prague or Cologne, but none of these cities can claim to host such a large breeding population. The main reason of this phenomenon might be the constant availability of prey all year round plus the security from human prosecution. Many birds even became accustomed to the presence of humans and became very trustful, thus offering great photo opportunities which are difficult to find elsewhere.
The first picture above shows a pair of goshawks during courtship feeding in March. In close vicinity of the nest, the male (left, notice red eyes and smaller size) deposits prey on a perch and subsequently attracts the female by calling her. Generally the male flies off before she approaches but this time, I was lucky to catch Mr. and Mrs. Goshawk smiling for the camera!
Kestrel on the CoverNov 26, 2013
One of my kestrel portraits made it on the cover of the NABU journal Natur in Berlin
. NABU (Naturschuzbund Deutschland) is Germany’s largest and oldest nature and bird conservation organization. The recent issue of Nature in Berlin
is a special volume featuring the astonishing diverse birds of prey occurring in the German capitol. Apart of the title page, the volume contains seven other of my raptor images. The complete contend can be viewed online here
Grassshopper SnackNov 25, 2013
During late summer and early fall, the Great green Bush-Cricket (Tettigonia viridissima) represents an important food source for the Eurasian kestrel, especially in years when voles are scarce. The grasshoppers are most active in the late afternoon and this is the hunting time for both, kestrels and photographers.
Interestingly, prey handling behavior differs much among individual birds: Whereas some kestrels manipulate and ingest their prey in flight, others prefer the comfort of a perch, usually a fence post. Generally, the first thing kestrels do after a successful catch is to bite off the head of their wriggly prey, thus preventing escape. Sometimes, however, they omit to do so, as in the case pictured above.
Front-lit YellowjacketNov 15, 2013
To create a pleasing halo of hairs around this German wasp (Vespula germanica) I used the frontal sunlight as the main light source and the Canon macro ring flash as a fill flash. The halo is best visble when a dark background is used. For this setup, I mounted a cardboard plastered with black velvet some centimeters behind the perch. Nothing absorbs light better than black velvet! To make the perch ( a plum) more attractive for the wasp, I trickled a mixture of water, honey and sugar on the reverse site of the plum.