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Migrating Birds Know No Boundaries. Proceedings of the International Seminar on Birds and Flight Safety in the Middle East, Israel, April 25-29, 1999

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Developing a Real Time Warning System in the Middle East; from Vision to Reality

Yossi Leshem
George S. Wise Faculty of Life Sciences
Department of Zoology Tel Aviv University
Ramat Aviv, Tel Aviv 69978, Israel

Abstract

The Middle East is strategically located al the juncture of three continents. As a result, it is a "bottleneck" into which all or a large part of the world population of certain soaring species concentrate during spring and autumn, as well as hundreds of millions of other birds. The concentration of an extremely large mass of birds has created a severe flight safety problem for Israel Air Force aircraft and its pilots. The Israel Air Force (IAF) has developed new flight regulations based on five years of research that have succeeded in reducing the rate of collisions with migrating birds by 76%. Following previous meetings with the Royal Jordanian (RJAF) and Turkish Air Forces it is proposed to develop a regional system of cooperation to be developed by each Air Force but based on one integrated regional system. The idea is to share the large experience gained in the IAF on these issues since 1984 and develop an information system on bird movements collected by a network of birdwatchers, radars and motorized glider flights. The data collected by Argos Satellite which intercepts radio transmitters attached to soaring birds will also be accumulated within this information system. EMC2, a leading data storage company, has already expressed its willingness to lead this idea.

The IAF is now in the process of purchasing weather and bird radars to develop a real time warning system. The Lockheed Martin radars as well as others arc being examined in order to cover the entire country with a network of these radars. It is proposed to develop a network of the same radars in other countries. Such a network will enable the Turkish Air Force in the autumn to provide real time information to the RJAF and IAF which can provide the real time data to the Egyptian Air Force. During spring migration, information will be transferred vice-versa from Egypt to Turkey.

As a resolution of this seminar it is proposed that each Air Force will join forces with local universities as well as bird and nature conservation organizations to establish new regional working groups and work to advance regional cooperation. The USAF and other airforces training in the Middle East will be invited to join this initiative.

'...On the path which no eagle knoweth, and which the honey buzzard eye hath not surveyed... " (Job, 28:7)

Introduction

The impressive sight of migrating birds over Israel, in spring and autumn, has already been noted by our ancestors ("Yea the stork in the heavens knoweth her appointed times; and the turtle dove and the swallow and the crane observe the time of their coming", Jeremiah, 8:7).

Israel's location at the junction of three continents - Europe, Asia and Africa - has made it a passage route of international importance for migrating birds of prey and large soaring birds, such as storks and pelicans, both in spring and autumn (Leshem & Yom-Tov, 1996 a,b).

Migrating birds can be divided into two principal groups: those flying actively and those using their gliding abilities (passive flight). The difference between the two groups arises from the changes in the relation between body weight and wing area as the bird grows heavier. The former increases to the third power, whereas the latter only squares itself. Thus, the heavier the bird, the more difficult it is for it to create lift in active flight by muscle power alone. The transition from one group to the other is gradual and a gradient exists between the small, actively flying birds, and the large soaring ones who can reach a weight of 15 kilograms. Most birds fall into the first category, such as the passerines (Passeriformes), waders (Charadriformes), and many other avian orders. They use fast wing beats to migrate for hours at a time. These birds are also called "sea crossers", since they can fly across large water bodies (such as the Mediterranean) or deserts, in active flight, for many hours, with no rest periods along the way. One of the better known examples is the Quail (Coturnix coturnix), which concentrates in large flocks in southern Europe, southern Turkey, the southern Aegean Peninsula and Italy, preparing to migrate. Before dark, the Quails depart, in order to cross the Mediterranean in one night, thus avoiding a long, roundabout route of hundreds of kilometers.

Large bodies of water, such as the Mediterranean, the Caspian, or Black Sea are an impediment to most soaring birds. They must circumvent them on their way from Asia and Europe, since there are no rising air currents (thermals) over water bodies. As a result, the western European population concentrates over the Straits of Gibraltar (Cramp and Simmons, 1980; Bernis 1980). A small part of the soaring bird population of central Europe crosses the Mediterranean at its narrowest points. The majority of the northern, central, and eastern European populations as well as large parts of the western Asiatic and Caucasian populations, fly along the shortest route which circumvents the Mediterranean. They concentrate in the skies over Turkey, Lebanon, Jordan, and Israel on their way to Africa. There is good reason for some of the birds of prey to lengthen their migrating route by hundreds of kilometers, avoiding the Mediterranean, by doing so, they achieve maximal energy conservation. Most large raptors, to whom we can add storks and pelicans, are heavy and have long, broad wings which are perfectly adapted to gliding. Due to their large body weight, these birds are unable to fly actively for days at a time with continuous wingbeats as do passerines, for example. They must, therefore, use flight routes over geographical areas where good soaring and gliding conditions exist, making use mainly of rising hot air currents. As a result, raptor migration is concentrated along narrow, long valleys, cliffs and long mountain ranges, where ideal gliding conditions develop, which allow these birds to progress with minimal energy expenditure.

With the help o their long, wide wings, the soaring birds lift off, circling around an invisible axis in the sky, on almost stationary wings, to an altitude where the air mass stops rising. At this point they start gliding, losing heights along the way (see fig 1), until they locate the next thermal visually, (by spotting other raptor or stork groups rising on a "neighboring" thermal), or aided by the extreme sensitivity of their wings and bodies to all changes in air currents.

Pennycuick (1972), compared the migration strategy of the white stork; (Ciconia ciconia), as a representative of soaring birds, and that of Bonellli's Warbler (Phylloscopus bonelli) as a typical actively flying bird. His data shows that with the stork, the relation between fat consumption during active flight to that in passive flight is 1:23. In the warbler the relation is a mere 1:2.4. This explains the tremendous significance of passive flight to large soaring birds.

Mountain ranges along the coasts of seas or large lakes, are ideal for the formation of rising warm air currents. As a result, the major migration routes in North America lie along three high mountain ranges, which are parallel to the eastern coast (Heintzelman 1986; Kerlinger 1989).

The advantage of Israel and Jordan as an ideal route for migrating raptors lies in its geographical location. The Syrian-African Rift runs the length of the countries, creating optimal conditions for rising thermals, since in this area, it is narrow and altitude differences reaching hundreds of meters exist along the Fault Escarpment. The combination of steep cliffs cut by narrow gorges and the high average temperatures along the Rift, provide a classic migration route for birds of prey and storks. The Lebanese mountains, the Shuf mountain rage, the mountains of the Galilee, Samaria, and Judea lie almost parallel to the coastline. This situation also creates good conditions for thermals, which facilitate soaring bird migration.

For the above reasons we can conclude that actively migrating birds:

1. Migrate both during the day and at night

2. Use direct and relatively short routes to migrate from breeding areas to wintering areas.

3 Cross large bodies during migration.

4. Store fat before leaving, since active migration uses large amounts of energy.

5. Migrate along a "broad" front and do not concentrate along defined, narrow migratory routes.

We can conclude that "passive" migrants:

6. Migrate only during the day.

7. Increase the total distance covered by migrating along routes with appropriate wind and thermal regimes.

8. Avoid crossing large bodies of water.

9. Do not accumulate and store fat before migrating, since passive flight is very economical energy wise.

10 . Migrate along defined and relatively constant routes.

The results of soaring bird migration tracking during the last three decades, both in the Old (Porter and Willis 1985, Bijisma 1987) and New World (Heintzalman 1986, Kerlinger 1989), confirm the above. They all show large soaring bird concentrations converging into straits, in order to avoid crossing water bodies.

Israel's unique location at the junction of three continents makes it an international crossroads for migrating birds: some 500 million birds cross Israel's skies heading south to Africa in autumn, and then flying north to Europe and Asia in the spring. The convergence of such a tremendous mass of soaring birds, some arriving in concentrated waves of tens and sometimes hundreds of thousands a day, over the limited air space over Israel, has created a severe flight safety problem for Israel Air Force (IAF), aircraft and pilots. The situation worsened significantly when Sinai was returned to Egypt in April 1982. Israel Air Force activity now had to concentrate within the new, narrower borders of the country. Analysis of fighter aircraft-bird collisions in the Air Force between 1972-1982, brought to light five important facts: (a) There had been hundreds of collisions with birds during these years. (b) A high percentage of the collisions occurred during the main migration months - in spring from March - May, and in autumn from August to November. (c) 74% of the most serious collisions, in which aircraft crashed or were seriously damaged (more than a million dollars), occurred during the migration months. (d) Damage due to migrating birds during the past ten years has cost tens of millions of dollars.

The following data emphasizes the dangers of bird-aircraft collisions:

1. A raven weighing 450 grams, hits the windshield of a car moving at 80 km/hr with a force of 150 kilograms.

2. This same raven, colliding with a fighter aircraft flying at 800 km/hr hits it with a force of 15 tons.

3. A Black Kite weighing about 900 grams hits with a force of 22 tons.

4. A Griffon Vulture, weighing about 6 kilograms, hits with a force of about 50 tons.

5. A White Pelican, weighing about 10 kilograms, hits with a force of 100 tons.

Aircraft-bird collisions are an international problem. However in Israel, due to its unique geographical location, the problem is especially serious, despite the small size of the country. Hundreds of IAF aircraft in such a small airspace along with the millions of birds migrating through this same space for six months each year, have caused many collisions. Until 1983, the IAF made no special effort to solve this problem.

In March 1983, I contacted the Flight Safety Wing of the IAF for permission to use a Cessna aircraft to track high altitude migration routes. At the first meeting with the Air Force officers we were told of the serious damage done by migrating birds. As a result, we started a joint study by the Israel Air Force, the Society for the Protection of Nature in Israel (SPNI) and Tel Aviv University, which was done in the framework of my doctoral thesis. I planned to do research whose conclusions could be applied operationally in the Air Force exercises, in order to significantly decrease the probability of aircraft collisions with migrating birds. The Air Force commander had given flight safety top priority at that time.

The objectives of this study were to find answers to the following questions: 1.I Is the number of birds appearing each year and each season (spring and autumn) constant? 2. Is the time of appearance and length of the migration wave constant each year and each season? 3. Are the migration routes over Israel (horizontal plane) constant on a daily seasonal and yearly scale? 4. ls there regularity in migration altitude (vertical plane) and velocity? 5. How do climatic and biological factors influence variations in this system? 6. Is it possible to predict variations in migration characteristics and implement those predictions in the Israel Air Force?

Methods

Five different data gathering methods were used for this research;

1. Ground Observing Network. A majority of studies have tracked migration with small numbers of observers at 2-3 key observation points. In this study, for the first time ever, ground observers were placed along a broad front: 25 observation points were placed across the country, along 75 kilometers from the Mediterranean coast up to the Rift Valley, during several migration seasons. More than 150 experienced birdwatchers logged about 224,000 observation hours. The system is still working continuously, to the present.

2. Light Aircraft Tracking - this method proved excellent for locating principal migration routes, their altitudes and counting flocks per time and distance units and proved to be very efficient on "peak" migration days. Additional flights were carried out to confirm the radar distinction ability (see method 5). Twenty-nine flights totaling 83:40 hours were carried out.

3. Motorized Glider - This method enabled continuous flying, up to 11.5 hours, with the same flock, as well as exact mapping of the migration route, altitude, flock progress rate, climbing and gliding in thermals. One hundred and seventy three flights totaling about 720 hours were carried out. This was the first time motorized glider migration tracking was used in the Middle East. No study using a motorized glider to systematically follow migration flocks for such long periods of time had been done up to now, both in the number of flight hours and the number of tracking days.

4. Unmanned Aircraft (Drones). This method enabled tracking single flocks for about 150 kilometers with constant documentation of the flock by video camera. Nineteen flights were carried out. To the best of our knowledge, this is the first biological study ever to make use of this military instrument for research.

5. Radar - A surveillance radar at Ben Gurion International Airport (ASR-8) was permanently available during the migration seasons. This enabled constant tracking during all hours of the day. The cloud radar of the Shaham Company followed migration regularly only during one season. Its use was terminated due to technical problems. A total of 8125 radar tracking hours were carried out. This is the first time radar was used to follow soaring bird migration in the Middle East and in Israel specifically. The system is still working continuously to the present.

Most migration tracking research has been limited to one method, and only a minority combined two methods simultaneously, such as a combination of radar and ground observers (Evans & Lathbury 1973) or light aircraft and radar (Pennycuick, Alerstam & Larsson 1979). In our study, we have developed, for the first time, to the best of our knowledge, research based on a combination of five methods for data gathering from one migration system, with each method complementing, at least partially, the deficiencies of one of the others. At the same time this enabled confirmation of research methods by integrating the various methods. The radar could, for example take over from the motorized glider for a short period of time to enable refueling and rest, it could then direct the glider to the exact position of the flock it had left to continue tracking.

The statistical analysis in this research is based on nine autumn migration seasons for raptors and four for storks and pelicans. During spring migration raptors were followed in Eilat for six years and storks for four in the western Negev.

Results

Producing a Map of the Bird-Plagued Zones

From the reservoir of data which were collected and analyzed, we were able to draw a map of the Bird Plagued Zones (BPZ) delineating the routes taken by the major concentrations of birds. Fighter planes have been forbidden to use these routes at low altitudes, except for take-offs and landings. Research data revealed that the masses of soaring birds are concentrated, on most days, at altitudes up to 3000 feet AGL, and the permitted altitude for fighter planes was regulated accordingly. It was recommended that carrier planes fly at lower speeds within the limited areas.

Predicted times for the start and end of the migratory season are printed on the map. Various colors are used to show the areas where different varieties of birds appear on different dates,. for instance: Large masses of storks migrate south along the Afro-Syrian Rift as early as August, while the great wave of birds of prey arrives only at the start of September, flying primarily along the parallel route to the west. The map also carries detailed instructions for planning flights during the migration season and for dealing with any sort of collision with the birds.

Two separate maps were published, one for the spring migration season and one for the autumn (see Fig 2) and the written procedures, known as the BPZ Regulations became part of the IAF's official codes. The maps are distinguished by high quality color print meant to stand out and attract the eye of every pilot when they are hung, according to orders, in the briefing rooms of every air squadron.

Marketing the Bird Issue and the BPZ and "Selling" Them to the IAF

During the course of our research, an elaborate program was introduced into the IAF to raise pilot consciousness about birds and the IAF's conflicts with them. A course of lectures accompanied by films and slides was delivered in all air squadrons and to other IAF personnel, such as radar units, who are involved in flight systems. The IAF also produced, in cooperation with the SPNI, a series of color posters on the subject along with calendars, stickers, explanatory pamphlets, and a vide cassette series which was distributed to all flight squadrons during every migratory season. Thanks to this "marketing" program and the new army regulations, the bird issue has become an important part of IAF conciseness within an unexpectedly short time.

Establishing the Birdwatching Center at Ben-Gurion Airport

In order to establish a single center which could collect all relevant data regarding movement of birds from all the sources of information and to distribute this information in real time to all parties in the IAF who might need it, we established the Birdwatching Center in the control tower of Ben Gurion Airport. It is currently run 24 hours a day by an SPNI employee and biologist and by four IAF radar specialists. A direct, private telephone and fax line near the radar screen ensures that the information is relayed smoothly and quickly. Input comes from the network of ground observers, aircraft (motorized glider and civilian and military planes) control towers of IAF bases, and radar control units. The Birdwatching Center provides ongoing information about flocks of birds located by radar which were flying in close proximity to IAF air bases or the approaches to them. We also developed a procedure to calculate the speed of the migrating flocks to deliver near real time warning event to those Air Force bases which are out of the Ben Gurion radar system range. When huge flocks few over shooting training areas, a real-time warning is given to the IAF control center to close the area in real time until the flock completely passed by. On days of heavy migration, warnings were also delivered to IAF radar control units to call off flights even outside the BPZ. Since some of the Air Force's largest bases are locate din the center of BPZ with a high number of landings and take-offs this real-time information was highly effective. Officers in the control towers thus had the opportunity to change the direction of landings and take-offs according to information about the birds' routes which was provided by the Birdwatching Center. On days with low migration, we permitted low altitude flights in the BPZ, depending on the high reliability of radar to immediately signal any new flocks approaching.

Operation of the Birdwatching center is critical because, during each season, there are a few days with dramatic changes in wind direction and speed. These changes such as NW winds becoming southerly or SE push the flocks out of the BPZ. In such cases the Center provides immediate reports to warn the whole system of the changes in real time.

The Birdwatching Center begins its Real Time Warning System activity on August 1 for autumn migration and on March 1 for spring migration (in each case, two weeks before heavy migration is expected to begin). The activity ends on November 30 and May 30, two weeks after heavy migration usually ceases.

This procedure allows us to follow the migration from the moment it starts to build up in significant numbers and to provide warnings about the presence of smaller flocks flying through which do not necessitate putting the BPZ regulations into effect. The final two weeks of the Center's season give the IAF the opportunity to fly at low altitudes, with no limitation in the BPZ with the understanding that the Center will provide real-time warnings about small flocks which are still present and might cause problems.

Final Results

Since the BPZ regulations and Real-Time Warning System were put into effect, the number of air collisions with migrating birds has fallen dramatically. In the 17 years since we began the operation the lAF lost two aircraft due to collisions with migrating birds, and there was a reduction of 76% in severe air collisions, saving the IAF approximately 450 million US dollars since 1984.

From Local To Regional Activity

During the last few years the peace process has gained real momentum. Following the peace process in 1982 between Israel and Egypt, a peace agreement between Jordan and Israel was signed, relations with Turkey were significantly strengthened and a new era of close relations between the Air Forces was developed. The IAF as well as NATO and United States Air Forces train in Turkey leading us to the idea of expanding the local flight safety programs to a regional level. We believe that flight safety and birds, which know no political boundaries (as a migrating stork or eagle can cross in one day three to five countries in the Middle East) can be an effective tool to share our experience and improve relations between the pilots and people through the common interests of safer flights and the protection of birds. Several bi-lateral meetings between the different air forces in the last three years brought us together in April 1999 at the seminar to discuss how to develop a real time warning system in the Middle East. A few subjects are proposed to advance the potential cooperation between the Jordanian, Turkish, Israeli and US Air Forces (and hopefully the Egyptian Air Force as well as others in the future) .

The International Center for the Study of Bird Migration at Latrun, Israel

As migration research in Israel intensified, in 1995 the SPNI and Tel Aviv University initiated the establishment of the International Center for the Study of Bird Migration at the Armored Corps Memorial in Latrun.

In the heart of Israel, at the foot of the Jerusalem Hills overlooking the Ayalon Valley and the Coastal Plain, midway between Tel Aviv and Jerusalem next the main highway (Route 1) and 18 km southeast of the Ben Gurion Airport lies Latrun.

The Latrun area is renowned since the days of the Bible in the adjacent Ayalon Valley, Joshua fought the famous battle during which "the sun stood still, and the moon stayed" (Joshua, 10:12) and many years later Judah Maccabee fought the Battle of Emaus nearby. It was also one of the most important crossroads in the Middle East, where the roads from Jaffa to Jerusalem and from Gaza to Ramallah and Damascus, met. Close to the site is one of the largest Crusader castles in the Middle East. The Israel Armored Corps established a memorial at Latrun to honor the memory of the 4,862 Armored Corps soldiers who gave their lives in Israel's wars. The memorial includes a museum with an open-air exhibition of 150 tanks, one of the largest of its kind in the world. The site, with its unique history and convenient location attracts many visitors. In 1998 alone, about 400,000 people - families, soldiers, schoolchildren and tourists - visited the site. Latrun is located at the very heart of the western migration route, which lies along the foothills of the Judean and Samarian Mountains.

The board of the Armored Corps Memorial at Latrun have allocated Tel Aviv University and the SPNI an area of eight acres on the western side of the site for the establishment of the International Center for the study of Bird Migration. Tel Aviv University currently leads the research institute at the complex and will hopefully be joined in the future by other academic institutions so the center will become an inter-university project. An MRL-5 weather radar, purchase din Russia, was brought to Latrun in 1996 and is operated by Dr. Leonid Dinewitz, a Jewish Russian general, who immigrated to Israel from Moldavia.

A 200-seat auditorium and an interactive museum will be built at the site. Visitors will be able to hear, see and actively participate in exhibits illustrating the theme of migration, the joint research project with the IAF and how peaceful coexistence between migrating birds and aircraft was achieved.

A joint educational center for the Armored Corps Associations and the SPNI is now being build and will have 50 rooms, classrooms and a dining hall for students, soldiers and nature lovers from Israel and abroad.

The conceptual purpose of the project is to combine history - the Armored Corps Museum and the battles fought around Latrun in the past - with the future: bird migration, flight safety, environmental protection, eco-tourism and education.

A regional network of bird and weather radars

Radars were developed for military purposes in order to control air traffic and locate aircraft. The greatest advantage of the radar is its ability to identify diurnal as well as nocturnal migration, and to follow migration at high altitudes beyond the scope of observers on the ground. Researchers previously used existing radar system developed for five main goals. 1) Military use and air traffic control 2) Anti-aircraft fire system radars 3) Airport surveillance radars 4) Weather radars for predicting climate changes 5) marine radars.

Civilian air traffic, as well as military flights, have increased significantly during the last decades. Military air forces now fly at low altitudes during day and night, using fire zones in several countries. The cost of commercial and military aircraft has increased two fold during the last decades. Due to these reasons, the potential for damage caused by birds has increased drastically.

Over the past three decades a number of articles on migration research by radar have been published (Gauthreaux 1970, Richardson 1975, Kerlinger 1989, Bruderer & Liechti l 995, Buurma 1995, and others). Following several meetings of the International Birds Strike Committee (IBSC) it became necessary to produce a publication on the application of radar for bird migration research. Buurma and Bruderer (1990) produced a comprehensive booklet on this subject which summed up the problem very well, general aspects of bird detection by radar, different types of radars and their suitability for bird observation and operational use. We propose the development of a regional network to predict bird movement at the same level as has been achieved in weather prediction.

Networks predicting changes in weather have improved significantly in the last 20 years. The networks are based on weather radars, satellites and worldwide databases. The US government has invested $2.7 billion in a joint project of the Federal Aviation Administration (FAA), National Weather Services (NWS) and the Ministry of Defense in creating a network of 165 NEXDRAD radars (new generation Doppler radar) model WSR-88 D, replacing the older model WSR-57 radars. The NEXRAD radars are located at airports and weather stations, covering the entire US.

Radar has proven to be an extremely effective operational tool for use warnings statements and short term forecasts. This is because, in part, it provides complete coverage of the volumetric area surrounding the radar out to 248 NM (460 km) and to an altitude of 60,000 ft (20 km) AGL at five minute intervals, three moments (reflectivity, mean velocity and velocity spectrum width) algorithm processing products totaling more than 75 displayable forms. In addition, the system is designed with considerable operational flexibility and capability. However, with this quantum leap in capability comes the necessity for effective management of system resources, careful product selection, and rapid recall time interpretations resulting in correct decisions and actions. Alden Electronics. Inc. has been selected by the NWS as a NEXRAD Information Dissemination Service (NIDS) provider. In conjunction with that service, Alden had developed the ALRAD II software, which provides the capability to access and display data from a network of NEXRAD Radars. Through Alden Electronics everyone can have complete access to the data.

Larkin & Quine ( 1988, 1989) studied the possibility of implementing bird recognition algorithms in the large S-band pulsed Doppler radars. The radars are equipped with a narrow beam and great power (1 megawatt) and sensitivity (90 dB dynamic range). Apart from the radar data acquisition subsystem it includes a radar products generation subsystem and a principle user processor sybsystem. Digital NEXRAD weather data are automatically processed by large computer programs but in periods without sever weather the system has the optional capacity to offer considerable processing time to run special bird programs. It is thought that it has the option of bird information every 5-15 minutes. Calculations show that a single herring gull would theoretically be visible as a faint target at a distance of 450km (But, of course, never will fly high enough to ascend above the radar horizon). Songbird echoes during migration often extend to beyond 100 km.

The researchers expect to be able to devise algorithms allowing NEXRAD to automatically distinguish echo patterns of weather and birds according to: 1) the speed of the birds, 2) their appropriate migratory directions, 3) the time of day of their flying activities, 4) their relations to topography and 5) certain echo characteristics. The plans were to let NEXRAD radars report bird hazard in different altitudes over the entire USA. Unfortunately, the involvement of the bird issue in the developing programs of NEXRAD system was stopped and the algorithms for birds detection did not receive the high priority they deserved. To the best of our knowledge the NEXRAD weather radars are a success story for weather usage, but the enormous potential for detecting bird movements is only now starting to be utilized by either the United States Air Force (USAF) or the FAA.

Since 1992, Prof. Gauthreaux has been following the migration recorded by 14 NEXRAD radars along the astern coast of the USA, while also using moon watching, marine radar, and others direct visual means. Gauthreaux believes (Pers. Com.) that the data gathered by the continental network would be unmatchable in the detail that it provides (see pictures 3-4).

A daughter group producing NEXRAD radars was created in East Asia. 14 radars have already been ordered and there is no doubt that in the coming decade a wide network of NEXRAD radars will develop in East Asia.

Following the fatal air collision of an F-15 with three white storks on 10 August 1995 in the Negev Desert, Israel, in which both the pilot and the navigator were killed and the aircraft destroyed ($50 million damage), the IAF Chief of Staff is now investigating which radar to purchase, and a decision will be rendered by the beginning of the coming millennium.

We proposed that following the installation of the network of radars in Israel, a regional radar program can be developed with other Middle East countries (see figure 6). We proposed to solve flight safety problems on a regional level, which will be much more effective than local systems. This regional system (see figure 6) would allow for real-time warnings between countries; for example, during autumn migration Turkey will warn Jordan (and hopefully in the future Syria and Lebanon) will warn Israel of migrating flocks, and Israel will in turn warn Egypt. During the spring migration, the same system will operate in reverse : Egypt-Israel-Jordan-Turkey. We already know from our satellite research that migrating storks can start a day in Egypt, cross through Israel and Lebanon or Jordan, and end the day at roost in Syria. The detailed migratory research which has been carried out in Israel can be expanded to Jordan, Turkey and Egypt; this research involves motorized gliders, networks of birdwatchers, radars and drones. The results will help to establish a regional database and a regional real-time warning system, as well as a bird avoidance model (BAM). The network of bird radars will also serve as weather radars, an eco-tourism real-time data source providing information on where to watch the birds and as a very important tool for the formal education system.

An operational plan for development and cooperation regarding these concepts appears at the end of these proceedings as was decided by the participants of the seminar.

Following Soaring Bird Migration by Satellites

Joint German-Israeli research on bird migration has been conducted since 1994 and funded by the German Ministry for the Environment, Nature Conservation and Nuclear Safety. The project is a cooperative venture between the Mx Planck Institute, Vogelwarte Radolfzell in Germany, Tel Aviv University and the SPNI in Israel. Research focuses on migrating white storks and uses satellite transmitters to follow the birds and track their migration routes.

In 1984, modern technology first made it practical to use satellites for tracking birds, with the development of transmitters small enough o be carried by a medium sized bird without interfering with its normal behavior and ability to fly. Every 90 minutes the location of the bird can be identified across the entire globe. Through Internet the data can be accepted everywhere almost in real-time and help advance the real-time system as a regional project. Ninety two storks were followed by satellite and we are now involved in a few more projects with migrating ospreys, wintering cranes and resident griffon vultures which are moving through the Middle East (see enclosed maps).

Bird aircraft conflicts in air bases

This is a very well investigated issue and many papers have been published in the biannual proceedings of the International Bird Strike Committee (IBSC) - formerly called the Bird Strike Committee Europe (BSCE). This subject which concerns all air forces is also discussed in one paper in these proceedings (Shy et.al.). We are showing a few pictures exposing some new techniques are now being considered all over the world.

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