White Storks in Armenia: Population, Trend, and Relationships to Humans
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WHITE STORK POPULATIONS ACROSS THE WORLD White Storks in Armenia: population, trend, and relationships to humans Karen Aghababyan, Maro Kochinyan, J.C. Lyman, L. Stepanyan, Acopian Center for the Environment (ACE) Zusammenfassung Over the 3 years, the mean productivity ranged from 2.33 to 2.59 Zwischen 2005 und 2007 sammelten wir in Armenien Daten von young fledged per nest. The number of young fledged per nest has 993 Weißstorchnestern. Die meisten Nester befanden sich in der increased: the number of nests with four fledglings has increased Ararat Niederung (87% der Nester im Jahr 2007). Die Zahl der (63 in 2005, 98 in 2006 and 125 in 2007), while the number of Brutpaare stieg von 548 HPa im Jahr 2005 auf 601 HPa 2006 und nests fledging only two young has decreased (195 in 2005, 165 in 624 HPa 2007 an. Der Brutbestand während des letzten Weiß- 2006 and 150 in 2007). storchzensus im Jahr 1984 war mit 668 HPa höher. Dies wird mit möglichen Doppelzählungen von Nestern im Jahr 1984 in Ver- Nest site choice has also changed: in 2005-2007, 818 (82.4% out of bindung gebracht. Es kann sich aber auch um einen realen Rück- total number of observed nests) nests were placed on pylons, com- gang infolge der Zerstörung von Feuchtgebieten in der Zeit der pared with only 335 nests (50.1% out of total number of observed Sowjetunion handeln. nests) in 1984. During the study period, 115 nests were destroyed: of these, 61 nests (53%) were destroyed by wind and 25 nests (21.7%) Der durchschnittliche Reproduktionserfolg (JZa) lag zwischen by fire (due to electrical short circuit). Nests placed on roofs of 2,33 und 2,59 Jungen pro Nest. Die Anzahl von flüggen Jungvö- houses cause damage by blocking the drainage pipes in the roofs. geln pro Nest stieg an: die Anzahl von Nestern mit vier flüggen Conservation measures were directed at improving the relation- Jungvögeln hat zugenommen (63 – 2005; 98 – 2006 und 125 – ship between humans and storks, by providing special nest-plat- 2007), während die Anzahl mit nur zwei Jungen abgenommen hat forms for the roofs of houses, rehabilitating injured Storks, and (195 - 2005; 165 - 2006 und 150 - 2007). recreating the Storks as a national symbol of Armenia. Die Nistplatzwahl hat sich seit 1984 verändert. Im Zeitraum zwi- Methods schen 2005 und 2007 wurden 818 Nester (82,4%) auf elektrischen Strommasten gefunden, während es noch 1984 nur 335 Nester The research data were collected during 2005 – 2008. The stu- (50,1%) waren. Während der Untersuchungszeit wurden 115 dy area includes the Ararat, Armavir, Aragatsotn, Yerevan, Lori, Nester zerstört, davon 61 Nester (53%) durch Wind und 25 Nes- Shirak and Vayots Dzor marzes (regions) of Armenia (see map on ter (21,7%) durch Feuer infolge eines elektrischen Kurzschlusses. Fig. 1). Data collection involved 167 expeditions lasting a total of Storchennester, die auf Hausdächern gebaut wurden, blockierten 245 days. In total, we visited 245 locations, and detected nests in die Regenwasserrinnen und verursachten so Schäden an der Bau- 116 of them. substanz des Hauses. Die Schutzmaßnahmen zielten darauf ab, das Verhältnis zwischen den Weißstörchen und den Menschen zu Data from 983 White Stork nests were collected during our visits verbessern. So wurden spezielle Nestplattformen für Häuser auf- in the spring-summer season, via direct observations and with the gestellt und verletzte Störche gepflegt. Außerdem wurde mithilfe assistance of village inhabitants (“nest neighbors”). Usually, nest einer intensiven Öffentlichkeitsarbeit versucht, den Weißstorch neighbors are those people who live closest to the storks’ nests. wieder als ein nationales Symbol von Armenien zu etablieren. To determine the number of White Storks in Armenia we used the method of complete counts by mapping each nest site. For every Summary nest we have fixed the following data: During 2005-2007 we collected data on 993 nests of White Storks y Geographical coordinates using GPS “Garmin 60CSx”; nests in Armenia, most of which (87.0% of pairs in 2007) are found in were classified as located on pylons or high-tension electricity the Ararat plain. In the years 2005-2007 we recorded an increase pylons, building roofs, trees, waterworks, statues, and cranes. in the number of Storks: in 2005, 2006, and 2007 we have recorded y Number of adult storks occupying the nest, and number of 548, 601, and 624 pairs respectively. The number of pairs counted fledglings. during the previous census in 1984 was higher (668 pairs), and it is unclear: is it result of possible duplcation during the 1984 count y Contact details for the “nest neighbors” (name and phone as a result of erros in methodology, or a real decrease might have number) been caused by wetland degradation during the Soviet period. y The year of construction of the current nest, the number of The data comparison suggests that there was some decrease in the young, and frequency of accidents to nests were all detailed breeding population of White Storks in Armenia after 1984, but with the help of “nest neighbors”, who also recorded causes an increasing trend during 2005-7. However, the apparent decrea- of nest destruction (wind, nest burning by electricity wires, se may be a result of differences in the methods used for the two etc), falls of nestlings and eggs from their nests, and deaths surveys. The 1984 study (ADAMIAN 1990) was carried out by of adult storks, etc. post: the author sent out simple questionnaires by post, with a request for these to be completed and returned. Using this me- y Details of any cases of conflict between storks and people in thod it is hard to avoid duplication of data. By contrast, our study the village. was carried out by mapping and providing actual counts of nests, which means that there is no duplication and only a very low like- The data collected by researchers and students from the Acopi- lihood of missing a nest. The increase during 2005-2007 may be an Center for the Environment (ACE) were recorded on special due to a short-term fluctuation, or part of a longer-term trend. To forms, while the observations of nest neighbors were recorded determine the specific cause we need longer-term (at least 10-15 on wall-calendars (Fig. 2) designed for our current study. Each years) monitoring of population. censused nest was numbered with a special label to assist with future monitoring (Fig. 3). The comparison of mean annual productivity throughout Arme- nia (Tab. 2) shows that the average number of fledglings per nest The combined methods of direct counting and data recorded by ranged from 2.33 to 2.59. In general, mean productivity appears “nest neighbors” allowed us to count almost all the nests in Ar- to be stable, with fluctuations in some years (e.g. in 2006), which menia, and to obtain comprehensive informations about breeding may be related to the abundance of prey species, but conclusions times, and breeding success. regarding general trends of breeding performance require lon- ger-term monitoring to be carried out. The collected data were stored in a Microsoft Access 2003 data- base (Microsoft Office 2003) for further data analysis. Statistical Nest locations analyses were carried out using Excel 2003 (MS Office 2003) and SPSS 11.0 for Windows (SPSS Inc., Chicago, II). The analyses In Armenia, White Storks build their nests on electricity pylons, included calculating mean breeding success and standard devia- roofs, trees, and sometimes even on monuments or non-opera- tions. Mapping and spatial analysis were conducted with ArcGIS tional cranes. We analyzed data for 993 nests (Tab. 3) and deter- GIS 9.2 (ESRI, Redlands, CA). mined that White Storks mostly breed on various types of electri- city pylons (82.4%), including: regular wood and concrete pylons; Results of the census 2005 - 2007 railway pylons; and high voltage iron pylons (Fig. 6). A total of 993 nests were detected during 2005-2007 in the Ararat, The second most frequent nest locations are roofs: storks pla- Armavir, Vayoc Dzor, Shirak, Lori, Aragatsotn and Yerevan mar- ce nests on roofs of schools and local administration buildings zes (regions) of Republic of Armenia. Of these, 548 were occupied (usually the tallest buildings in the village), as well as on roofs of by pairs and 32 by single birds in 2005, 601 by pairs and 36 by private houses. By building nests on roofs, storks can cause seri- single birds in 2006, and 624 by pairs and 21 by single birds in ous damage to houses, since they generally place nests on draina- 2007. ge system pipes that can then become blocked. The result is that moisture accumulates in the walls causing damage to homes (Fig. Distribution of White Storks in Armenia was not uniform (Fig.4). 7). Most of the nests are situated in the Ararat valley (543 pairs, 87.0% in 2007), while several small subpopulations inhabit Shirak Comparison of our data with data collected in 1984 (ADAMIAN (26 pairs, 4.2%) and Lori (40 pairs, 6.4%) plateaus and Arpa river 1990) suggests that, over the years, storks have shifted their pre- valley (15 pairs, 2.4%). ferred nest locations from roofs to pylons. Nest sites on pylons are vulnerable to fire (caused by short circuits), or wind. During The total output of fledglings in 2005 was 1,310 (from 545 nests), 2005-2007, we recorded 115 cases of nest damage. 61 nests (53%) 1,385 (from 594 nests) in 2006, and 1,615 (from 623 nests) in were destroyed by wind, and 25 nests (21.7%) by fire. Damage to 2007. Mean productivity (JZa = young fledged per pair ± SD) was nests was relatively low in 2005 (25 cases), but higher in 2006 (37 2.40±1.07 in 2005, 2.33±1.29 in 2006 and 2.59±1.26 in 2007 (Fig.