Nest and nidification behavior of Cattle Egrets (Bubulcus ibis coromandus) in and around the areas of Jammu (J&K, India).
The nesting activity is an important component of breeding behavior and breeding success. An appropriate nesting site plays a very eminent role in protection against predators and offering competent materials for the construction of nest thereby supporting the nest. Moreover, a good nesting site is always imperative for the accession of food so as to meet the demands of the nesting birds and afterwards nestlings too (Hafner, 1977; Thompson, 1977; Beaver et al.,1980; Hafner and Britton, 1983; Gibbs et al., 1987; Hafner and Fasola, 1992; Hafner, 2000) [1,2,3,4,5,6,7]. Furthermore, Ludwig et al. (1994) communicated the nesting site as an indispensable attribute for the promotion of hatching success and Buckley and Buckley (1980) have also considered the value of nesting site for the successful rearing of young which is important for the survival of individuals. The present communication encompasses the main objective to gather a firsthand information regarding the nest and various nidification activities such as the number of hours of labour for nest construction, the type and amount of nesting material collected during the busy hours of nidification, average time spent in gathering sticks for nest building, average time to carry the nesting material from its source to the nest, nest inspection and rearrangement activities by nest occupants to determine the role of both sexes of Cattle Egrets (Bubulcus ibis coromandus) in Jammu as virtually nothing has been reported pertaining to these aspects of the bird from the study area. The nests of the Cattle Egrets are designed to provide a controlled environment almost always simply to protect young ones. There is much noise in the nesting territory of Cattle Egrets which may act as an energetic defense so as to keep the nest safe from predators.
During the period of present study, the study area (Fig. 1) was divided into five stations:
* Station I (Tirlokpur, Gho Manhasa): The station is positioned at a latitude of 32[degrees] 43'27.79"N and a longitude of 74[degrees]44'21.12" E with an elevation of 265 meters from mean sea level. It falls in Jammu tehsil and is about 12km from Jammu city. At this station, the main source of water is Gho Manhasa Stream.
* Station II (Pounichak, Gho Manhasa): This station is situated between the latitude and longitude of 32[degrees]44'20.28"N and 74[degrees]47'58.49"E respectively. Its elevation from the mean sea level is 281 meters. It is at a distance of 14 km from Jammu city and falls in Jammu tehsil. Gho Manhasa stream is the main source of water at this station too.
* Station III (Gharana Wetland, R. S. Pura): It is situated between the 32[degrees]36'51.52"N latitude and 74[degrees]38'58.15"E longitude. It is located at an elevation of 251 meters from the mean sea level. This station is at a distance of 35 km from the Jammu city in Ranbir Singh Pura tehsil. At this station, the main source of water is Ranbir Canal.
* Station IV (Haripur, R.S.Pura): The latitude and longitude of this station are 32[degrees] 36'27.56"N and 74[degrees]43'57.29" E respectively and it is located at an altitude of 271 meters from mean sea level. The station is at a distance of 31 km from Jammu city.
* Station V (Army Cantonment, Nagrota): This station is positioned at a latitude and longitude of 32[degrees]46'33.86" N and 74[degrees]54'16.20" E respectively. Its height from the mean sea level is 351 meters. It is situated at a distance of 12 km from Jammu city.
[FIGURE 1 OMITTED]
MATERIAL AND METHODS
Stations I to IV fall under the category of outer plains of Jammu i.e. the areas of open cultivation. These areas were noticed to be well irrigated with the agriculture including predominantly of Oryza sativa (Rice), Triticum aestivum (Wheat), vegetables and fruit trees. Station V falls under the category of Kandi Area/Semi Hilly and there Triticum aestivum (Wheat) and Zea mays (Maize) were found to be the main crops in the small patches of cultivation.
Dominant Plant Species:
Acacia nilotica (Babul), Acacia modesta (Kramishatrav), Dalbergia sisoo (Sheesham), Morus alba (Shahtoot), Eucalyptus tereticornis (Safeda), Mangifera indica (Aam), Melia azadiracta (Vakayan), Ficus bengalensis (Barghad), Lantana camara (Kattu Hingu), Zizyphus spp. (Ber), Grewia optiva (Dhamin), Emblica officinalis (Amla), Vitex negundo (Nishigandha), Cassia fistula (Amaltaas), Butea monosperma, Carissa opaca, Lantana camara, Dedonea viscose etc.
The present study was carried out over two breeding seasons (2008 and 2009) from March to July by adopting systematic field procedures and techniques. Recurrent surveys of the stations were performed from 0630 hrs to 1200 hrs in morning and 1300 hours to 1900 hours in evening during summer and 0730 hours to 1200 hours in morning and 1400 hours to 1830 hours in evening during winter. The birds were observed with naked eye and through binoculars (Bushnell 7 x 50 U.S.A. made) whenever found necessary to record the data from quite a long distance in order to avoid any interference to birds due to the presence of observers. Photographs were taken with the aid of canon EOS camera fitted with 300 mm zoom lens, digital camera and video camera.
A nest is defined as any depression in which the bird lays one or more eggs (Miller and Johnson, 1978)  whereas an active nest was one that contained an egg or nestling in it. Shape, size, structure and position for each nest were recorded. Nest heights were measured with a measuring tape. Nest dimensions (maximum diameter, vertical thickness and nest depth) were recorded to the nearest centimeter and were expressed by means with standard errors (SEM) and proportions in order to compare them with other studies.
The data thus collected was subjected to statistical analysis using various statistical tests. Karl Pearson's Coefficient of Correlation tested at 5% level using Student-t-test was used to examine relationship between two nest variables. Total 250 nests were selected to test the hypothesis that middle canopy of the nesting tree harbours more number of nests in comparison to the lower and higher canopy of the nesting tree. Two-Way ANOVA was applied to compare the significance of the diverse nest parameters among the five stations. Correlation Coefficient, Chi-square test and Two-way ANOVA was calculated with the help of Microsoft Excel (MS Office, 2007) and SPSS Software (Ver. 16.0).
The Cattle Egrets started the nest building much before they had a mate and both the partners actively participated in nest building. The phenomenon of nest building in the study area was observed from last week of March to last week of April (2008 and 2009). However, the process of nest repairing was noticed to be continued even after the laying of eggs, during the process of incubation and after hatching i.e. it extended up to June, though the frequency of collection of nesting material gradually decreased with the above mentioned three stages.
The one partner usually male after acquiring the nesting territory depicted a diverse repertoire of "Breeding Displays" or "Courtship Displays" like Stretch Display, Twig Shake, Flap Flight, Wing Preening and Head Flicks at the nesting site. After visualizing the diverse "Courtship Displays", male approached the appropriate female at nest and mounted her and afterwards copulation or mating took place. It was observed that the partner which mounted the other partner was the same which depicted courtship displays.
Nesting Site Selection:
Upon arrival at the area, birds were observed to search and inspect the potential nesting spots in the territory. The birds began to fly over the entire nesting area and then selected a suitable place for nesting. This process took almost 4-5 days. After having claimed the nesting territory (an old nest site or a new nest site), both the partners of the pair bond took part in nest formation. During the two breeding seasons studied, the birds were not found to change their nesting sites. In the area under inquisition, the nesting colonies of Cattle Egrets were recorded to be exclusively monospecific with only Cattle Egrets nesting on the nesting tree. The nesting colonies were exclusively on trees within the close vicinity of human settlements and were located over a small area with the source of water approximately 5-30 meters away. Trees of Acacia nilotica followed by Mangifera indica were utilized for nesting by Cattle Egrets in the study area.
The placement of nests by Cattle Egrets was usually in a fork at the main trunk. The cluster of nests was noted both at the central position (Core Nests) as well as the peripheral position (Peripheral Nests).The percentage of Core Nests and Peripheral nests built on the Acacia was found to be 33.17% and 66.83% respectively (Table 1) whereas on the Mangifera indica the percentage was noted to be 71.11% and 28.89% respectively (Table 2). The average maximum height of the nests on Acacia nilotica and Mangifera indica was found to be 7.38 [+ or -] 0.94 meters and 4.58 [+ or -] 0.70 meters respectively (Table 3). The average minimum height of nests on Acacia nilotica and Mangifera indica was found to be 6.42 [+ or -] 1.05 meters and 3.84 [+ or -] 0.59 meters respectively (Table 3). The overall colony size was found to be in the range of 38 to 95 individuals.
Nest Composition, Structure and Dimensions:
Naked, dry and dead solid sticks were being predilected by Cattle Egrets but in case of unavailability of those materials, breaking live twigs off the nesting tree i.e. Acacia, using Typha sp. and dry grass were discerned most commonly for nest building. The dry and naked nesting material was mostly seen to be procured from the nesting tree itself i.e. Acacia and sometimes Parthenium sp. was also advocated for nesting purposes. The Cattle Egrets were recorded to collect twigs from the surrounding open area or from the old nests. Two basic strategies were employed by one of the two partners in placing the nesting material, firstly, while inserting the nesting stick into the framework of the nest, the bird executed a "Tremble-Shove" action where holding the stick in its bill, it pushed that slowly into the already woven lattice (shove) while shaking its head with a short lateral movement (Tremble). Secondly, while removing the stick from the lattice, it used a "Push-Pull" action, jerking that stick back and forth. Cattle Egrets were observed to construct multilayered circular platforms with the broad, dead, spiny, lengthy and stouter sticks at the base of the platform and soft, short, live and meek twigs on the top of the platform. Twig stealing behaviour by Cattle Egrets was also reported from the study area. No competition was depicted with other ardeids by Cattle Egrets in the matter of procuring nesting sticks in the study area as they were purely monospecific in the study area.
The range of length of the nesting sticks varied from 25 cm to 75 cm. A few nests were built on already existing old nests thereby leading to the formation of a very solid structure whereas mostly others were so loosely framed that the eggs could be seen through the lattice of sticks. The recurrence of collection of nesting material was deduced to be higher in the morning from 0730 hours to 1230 hours and then again from 1500 hours until sunset. As the day proceeded, Cattle Egrets used to visit the adjoining areas foraging for food. The average number of sticks collected per day during pre-laying period, laying period and post-laying period was noticed to be 25, 10 and 5 respectively. It was discerned that Cattle Egrets took 5-7 minutes on an average to search the nesting material and carry that material from the source to the nesting site. Average hours of labour for nest construction during busy period of nesting were noticed to be 6 hours/day.
The average inner and outer diameters of nests (n=50, at each station) were found to be 26.76 [+ or -] 2.65 cm and 22.99 [+ or -] 3.27 (St-I), 27.08 [+ or -] 3.21 and 32.70 [+ or -] 3.59 (St-II), 21.26 [+ or -] 2.50 and 25. 25 [+ or -] 2.84 (St-III), 21.52 [+ or -] 1.79 and 25.95 [+ or -] 2.09 (St-IV), 23.49 [+ or -] 2.84 and 27.83 [+ or -] 2.93 (St-V). Besides, average nest thickness and nest depth were recorded to be 6.45 [+ or -] 1.63 and 4.46 [+ or -] 1.38 (St-I), 6.16 [+ or -] 1.48 and 4.72 [+ or -] 1.14 (St-II), 2.58 [+ or - ] 0.65 and 4.50 [+ or -] 1.06 (St-III), 4.14 [+ or -] 0.90 and 4.57 [+ or -] 1.26 (St-IV), 4.19 [+ or -] 0.84 and 4.73 [+ or - ] 1.26. On the other hand, the average inner nest diameter, outer nest diameter, nest thickness and nest depth (in cm) for all the stations was found to be 23.45 [+ or -] 3.36, 28.27 [+ or -] 3.99, 4.70 [+ or -] 1.85, 4.59 [+ or -] 1.23 respectively (n=250).
Karl Pearson correlation coefficients (r) are shown in Table 4. The outer diameter of nest was deduced to be significantly related to the inner diameter of nest (r = 0.928, p < 0.05), nest thickness (r = 0.554, p < 0.05) and nest depth (r=0.252, p<0.05). Furthermore, two-way ANOVA registered significant variations in inner diameter of nest among stations ([F.sub.3,72] = 33.19, p < 0.05) but exhibited insignificant variation among different nests at the same station. Significant variations in outer diameter of nest among stations ([F.sub.3,72] = 50.51, p < 0.05) along insignificant variations among different nests at the same station was recorded along with the significant variations in nest thickness among stations ([F.sub.3,72] = 17.74, p<0.05) and insignificant variations among different nests. Also, there were significant variations in nest depth among stations ([F.sub.3,72] = 36.13, p < 0.05) and insignificant variations among the different nests at the same stations. Chi-square test deduced that the placement of nests was significantly associated with the canopy stratification ([x.sup.2] = 5.99, p < 0.05, n=250) thereby, drawing the conclusion that the middle canopy of the nesting tree harbours maximum nests as middle canopy is maximally prevented from predators.
During the two breeding seasons studied, the birds were not found to change their nesting sites. This may be due to the availability of plentiful food resources in the surrounding area and safety for nest and nestlings (Parasharya and Naik, 1990; Gadhavi and Soni, 2002; Yahya, 2001) [11,12,13]. Cattle Egrets were observed to nest on trees in rural areas as in case of stations I, II & IV; agro-ecosystems like station III and urban setup like station V depending upon the availability of food, water, safe nesting places, availability of nesting material and other environmental factors. Same vindication has been proposed by Gopal et al. (2004) , Mathew and Gadvi (2004)  and Rao (2004) . The phenomenon of nest building in the study area was observed from first week of April, 2008 to last week of April, 2008. This finding is contrary to that of McKilligan (2005)  who reported the nesting season of Cattle Egrets typically of five months, from October to March in Eastern Australia but similar to that of Cogswell (1977)  who reported the nesting season from April to July at Salton Sea. On the other hand, Kushlan and White (1977)  recorded that Cattle Egrets nest from March to October i.e. almost year around in Southern Florida. Nesting behaviour of Cattle Egret was recorded for the first time in the Indian Subcontinent by Ali in 1941.
Nest site selection acts as major factor in habitat selection by birds and is greatly influenced by food availability, presence of suitable nest material, protection from predators and suitability of area (Collias and Collias, 1984)  besides bird's nest building pattern/instinct as well as their early experience (Ali and Ripley, 1983) . The nesting trees opted by the Cattle Egrets in the area under inquisition were discerned to be maximally Acacia nilotica followed by Mangifera indica. The selection of Mangifera indica (Mango tree) in the study area was in agreement with that given by Mahabal (1990)  who divulged the nesting sites of Cattle Egrets to be Tamarind (Tamarindus indica), Mango (Mangifera indica) and some Ficus sp. However, Patankar et al. (2007)  notified Cattle Egrets to nest on Mimusops ellengi and Lagerstroemia sp.
Cattle Egrets used to occupy breeding or nesting territory which was afterwards used for courtship, nesting and copulation purposes. After the acquisition of a nesting territory, a diverse repertoire of "Breeding Displays" or "Courtship Displays" were noted at the nesting site, although the displays were not so elaborate. McKilligan (2005)  noted the various "Courtship Displays" depicted like Stretch Display, Twig Display, Flap Flight, Wing Preening and Head Flicks including some other breeding displays like Snap, Courtship Flight and Wing Spread along with some Pair Bonding displays like Greeting Display, Bob Display, Backbiting and Bill Clappering.
In the area under inquisition, the nesting colonies of Cattle Egrets were recorded to be exclusively monospecific with only Cattle Egrets nesting on the nesting tree. This observation, however, is antithetical to that of Ali and Ripley (1968)  and Maccarone and Parsons (1988)  who noticed Cattle Egrets to nest in the mixed colonies with Cormorants, Ibises and other members of family Ardeidae. But the above finding is in full consonance with the one made by Arendt and Arendt (1988)  and Patankar et al. (2007) . Moreover, the nesting colonies were exclusively on trees within the close vicinity of human settlements and were located over a small area with the source of water approximately 5-30 meters away. So, the heronries studied during the study period have been classified according to Singh and Sodhi (1985)  and can be described as under:
* Small Sized Heronries--As the colonies were located over a small area.
* Associated Type of Heronries--As the heronries were within the anthropogenic approach.
* Tree Type Heronries--As all nests of the heronries were constructed on trees.
* Monospecific Type--As only a single species was nesting in the heronry.
Furthermore, Burger (1978)  examined 14 colonies of mixed ardeid species in Argentina, Mexico and the U.S. and divided them into two types according to vegetation structure:
* Homogenous Colonies/Heronries--Those colonies which contained either a pure strand of one plant species or several species of plants so intermixed that every area of the colony looked alike.
* Heterogeneous Colonies/Heronries--Those colonies which contained dissimilar sub-areas with respect to plant species, density, height or amount and location of open spaces.
Thus, the heronries studied during the study period can be better designated as Heterogeneous Colonies/Heronries.
The dry and naked nesting material was mostly seen to be procured from the nesting tree itself i.e. Acacia nilotica and sometimes Parthenium sp. was also advocated for nesting purposes. The Cattle Egrets were recorded to collect twigs from the surrounding open area or from the old nests. Similar recordings were made by Mc Killigan (1990) . Iyer (2004)  has supported the use of only dry and naked twigs for nest building by egrets but Gopal et al. (2004)  had reported grasses being used in the nests by Cattle Egrets. Cogswell (1977)  had recorded the nests of twigs and small sticks built in dense canopied trees or tall shrubs near good feeding areas, usually beside aquatic or wetland habitats. The most plausible cause for selecting the dry and naked twigs in place of live ones may be that the dry twigs can be easily broken off from a tree as compared to live twigs thereby lessening the energy expenditure (Mc Killigan, 1990) . Cattle Egrets have also been reported breaking the dry twigs of certain trees namely the Copper Pod tree (Peltoforum pterocarpus), Nilgiri (Eucalyptus aromatica), Neem (Azhadirachta indica) and Gulmohar (Delonix regia) by Patankar et al. (2007) . McKilligan (2005)  divulged the nests of Cattle Egrets in the form of a multilayered circular platform with the dead, broad, spiny, lengthy and stouter sticks at the base of the platform and soft, short, live and meek twigs on the top of the platform. The most probable explanation for such a placement seems to be the provision of strength to the nests and safety from the predators. Moreover, it was recorded that two strategies for construction of nests were employed by Cattle Egrets namely "Tremble-Shove" action and "Push-Pull" action. This finding is in full agreement with that of Fujioka and Yamagashi (1981)  and Mc Killigan (2005) .
Twig stealing behaviour by Cattle Egrets had also been reported by Iyer (2004)  and Valentine (1958)  at Virginia. Moreover, Siegfried (1971 and 1972 a) [33,34] and Lancaster (1970)  had also viewed stealing of nesting material among Cattle Egrets themselves in Africa and Columbia respectively. No competition was depicted with other Ardeids by Cattle Egrets in the matter of procuring nesting sticks in the study area as they were purely monospecific in the study area. But, Burger (1978)  found Cattle Egrets more aggressive than other Ardeids and Ibises and usually having predominant access to the nesting sticks. Patankar et al. (2007)  professed that in the morning the collection of nesting material is higher from 0730 hours to 1300 hours and then again from 1500 hours until sunset. Mc Killigan (1990)  found average sticks collected per day during the three periods to be 24.8 [+ or -] 19.3, 11.5 [+ or -] 12.2 and 4.6 [+ or -] 7.1 respectively.
The average inner and outer diameters of nests (n=50, at each station) were found to be 26.76 [+ or -] 2.65 cm and 29.60 [+ or -] 3.13 (St-I), 27.08 [+ or -] 3.21 and 32.70 [+ or -] 3.59 (St-II), 21.26 [+ or -] 2.50 and 25. 25 [+ or -] 2.84 (St-III), 21.52 [+ or -] 1.79 and 25.95 [+ or -] 2.09 (St-IV), 23.49 [+ or -] 2.84 and 27.83 [+ or -] 2.93 (St-V). The average inner nest diameter, outer nest diameter, nest thickness and nest depth (in cm) for all the stations was found to be 23.45 [+ or -] 3.36, 28.27 [+ or -] 3.99, 4.70 [+ or -] 1.85, 4.59 [+ or -] 1.23 respectively (n=250) which was larger than the average diameter as reported by Arendt and Arendt (1988) and Patankar et al. (2007) . However, these average diameters are smaller than those reported by Siegfried (1971)  and Burger (1978) . The average nest thickness (n=50, at each station) was found to be 6.45 [+ or -] 1.63 cm (St-I), 6.16 [+ or -] 1.48 (St-II), 2.58 [+ or -] 0.65 (St-III), 4.13 [+ or -] 0.90 (St-IV) and 4.19 [+ or -] 0.84 (St-V) which was much smaller to that reported by Arendt and Arendt (1988)  and Patankar et al. (2007) . The average nest depth was noted to be 4.73 [+ or -] 1.26 (St-I), 4.72 [+ or -] 1.14 (St-II), 4.5 [+ or -] 1.06 (St-III), 4.57 [+ or -] 1.26 (St-IV) and 4.46 [+ or -] 1.38 (St-V).
The effect of nest location (central versus peripheral) on breeding success has been investigated by a number of workers. Central nests are presumably safer than peripheral nests but are possibly more exposed to aerial predators and strong winds (Siegfried 1972a, Si Bachir et al. 2000) [34,36]. Patankar et al. (2007)  noticed all the nests located on Mimusops ellengi to be peripheral in position occupying the entire canopy and those situated on the Lagerstroemia to be core in position. However, Vyas (2006)  have reported Cattle Egrets to nest at the peripheral and lower strata of a canopy in a mixed species heronry. The percentage of Core Nests and Peripheral nests found on the Acacia was noted to be 26.37% and 73.63% respectively and in case of Mangifera indica the percentage of Core nests and Peripheral Nests was discerned to be 56.67% and 43.33% respectively (Table 1). In case of Acacia, this is in contradiction with Arendt and Arendt (1988) who have reported nearly 53% of Cattle Egret nests to be Core Nests but in case of Mangifera indica, this is nearly in consonance with Arendt and Arendt (1988) .
From the observations, it can be concluded that the nest placement whether Core or Peripheral, to a great extent, banks upon the branching pattern of the nesting tree. As the canopy of the Acacia tree is such that there is less branching near the trunk region or core region and more at the peripheral region that is why the core region of this nesting tree provides room for less number of nests and Cattle Egrets constructed most of their nests at the periphery of the nesting tree after consuming the core space. Further, presence of the thorns on the trunk region provides ample safety to the peripheral nests from the reptilian predators. On the other hand, at station IV and V, the nesting tree was Mangifera indica and there were more number of nests present in the core region rather than on the periphery. This placement again depended upon the branching pattern of Mangifera indica which has more branching at the core region thereby providing more space for the nests and enough protection from the avian as well as reptilian predators. Iyer (2004)  has also detected Cattle Egrets preferring the core regions of canopy for nesting. After the occupation of core nest sites, Cattle Egrets constructed nests at the peripheral locations. The probable justification for the predilection of the core positions for the nest construction by the Cattle Egrets may be that the inner or core canopy is shielded from the attack of the various predators like House crows and Black Kites and other reptiles like snakes who are in habit of plundering and predating the chicks.
The average maximum and minimum height of the nests was found to be 7.38 [+ or -] 0.94 and 6.42 [+ or -] 1.05 meters respectively (Table 3). Burger (1978)  noted the mean nest height for Cattle Egrets in a colony in Mangroves at Lake Alice, Florida to be 2.38m where as Hilaluddin (2003)  recorded the mean nest height as 10.69 [+ or -] 1.38m in Amroha, Uttar Pradesh (India). Si Bachir et al. (2008)  noticed the placement of nests at a height of 4 to 15m. The overall colony size at all the stations was found to be in the range of 38 to 95 (Table 13) which was much smaller than that studied by Hilaluddin et al. (2005)  in Amroha, Uttar Pradesh who reported the colony size to be 550 in the year 2003 and 3812 in the year 2005.
Cattle Egrets preferred Acacia nilotica for nesting because of the suitable general morphology of the tree i.e. thorny structures present on the trunk and branches of the tree which provide protection against the predators. However, Patankar et al. (2007) notified Cattle Egrets to nest on Mimusops ellengi and Lagerstroemia sp., Hilaluddin et al. (2003) discerned majority of nests on Ficus benjamina, Ficus glomerata, Ficus religiosa with the placement occasionally on Mangifera indica, Pithecellobium dulce, Azadirachta indica and Delonix regia. This finding, however, is incongruous to that of Patankar et al. (2007)  who found all the nests located on Mimusops ellengi to be peripheral in position occupying the entire canopy and those situated on the Lagerstroemia to be core in position.
The information generated from this study gives us a clear picture pertaining to the conservation efforts needed to focus not only on protection of nesting colonies, but also on large scale preservation of adjacent foraging habitat. In the study area, public awareness and education programmes are needed to protect nesting trees and minimise disturbance in order to ensure long-term persistence of waterbirds in general and ardeids in particular.
The authors would like to thank Department of Zoology, University of Jammu, Jammu for providing necessary facilities to carry out the study.
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Deep Novel Kour (1) * and D. N. Sahi (1)
(1) Department of Zoology, University of Jammu, Jammu-180006, J&K, India. * Corresponding author: Email: email@example.com
Email of Prof. D.N. Sahi: firstname.lastname@example.org
Table-1: Number and percentage of Core and Peripheral Nests of Cattle Egrets on Acacia nilotica in the study area. Stations Number of Number of Number of Nests Found Core Nests Peripheral (n) Nests St-I 42 15 27 St-II 80 25 55 St-III 30 10 20 St-IV 32 12 20 St-V 21 06 15 Total 205 68 137 Stations Percentage of Percentage of Core Nests Peripheral Nests St-I 35.71 64.29 St-II 31.25 68.75 St-III 33.33 66.67 St-IV 37.50 62.50 St-V 28.57 71.43 Total 33.17 66.83 Table-2: Number and percentage of Core and Peripheral Nests of Cattle Egrets on Mangifera indica in the study area. Stations Number of Number of Number of Nests Found Core Nests Peripheral (n) Nests St-I 07 05 02 St-II 12 08 04 St-III 05 04 01 St-IV 16 12 04 St-V 05 03 02 Total 45 32 13 Stations Percentage of Percentage of Core Nests Peripheral Nests St-I 71.43 28.57 St-II 66.67 33.33 St-III 80 20 St-IV 75 25 St-V 60 40 Total 71.11 28.89 Table-3: Location of nests on the nesting tree, Acacia nilotica in the study area. Stations Nesting Trees Acacia nilotica Mangifera indica Height of Height of Height of Height of Tallest Nest Lowest Nest Tallest Nest Lowest Nest (in meters) (in meters) (in meters) (in meters) St-I 7.5 6.6 3.9 3.4 St-II 8.1 7.5 4.2 3.5 St-III 8.4 7.2 5.1 4.6 St-IV 5.7 4.5 4.0 3.2 St-V 7.2 6.3 5.7 4.5 Mean 7.38 6.42 4.58 3.84 [+ or -] [+ or -] [+ or -] [+ or -] 0.94 1.05 0.70 0.59 Table 4. Correlation Coefficients (r) between the diverse nest characteristics of Cattle Egrets (n=50) in the study area. Nest OD NT ND Characteristics ID ID 0.928 * 0.204 0.209 OD 0.554 * 0.252 NT 0.196 * ND where, ID = Inner Diameter of Nest, OD = Outer Diameter of Nest, NT = Nest Thickness and ND = Nest Depth. * marked were significant (p<0.05).