韓雪松 郭玉民

(北京林業(yè)大學(xué)自然保護區(qū)學(xué)院，北京，100083)

行為是鳥類的固有特征之一，鳥類的生存需求通過不同的行為表達來實現(xiàn)[1]。依照行為發(fā)生的動機和作用的對象，鳥類行為可以分作個體行為(Individual Behavior，or Non-Social Behavior)及社會行為(Social Behavior)。其中，個體行為是構(gòu)成鳥類一切行為的基本要素，亦是其行為的最關(guān)鍵組成部分[2]。個體行為在不同情景下或具有社會性的含義而同社會行為的界限并不清晰，有時亦作為復(fù)雜社會行為的一部分而出現(xiàn)[3]。因此，對于鳥類個體行為的描述是研究其復(fù)雜行為序列、社會行為乃至更深層次的行為機理的基礎(chǔ)，對其了解的程度將影響對其的研究以及保護工作的成效[4]。

鶴形目(Gruiformes)鳥類是古老的動物類群[5]，對其的行為學(xué)研究已有很多工作付諸實踐[6-10]。作為隨青藏高原隆起而形成的特有物種，黑頸鶴(Grusnigricollis)是鶴科(Gruidae)當(dāng)中適應(yīng)于高原嚴(yán)酷自然環(huán)境的獨特一支[11-12]。在黑頸鶴的行為學(xué)研究上，目前已有工作多局限于行為描述及時間分配等方面[13-28]，而對個體行為——特別是其分級分類——并未得到充分的探索，僅有的研究也局限于籠養(yǎng)個體[3，17]。系統(tǒng)的個體行為分類體系的缺乏導(dǎo)致已有行為學(xué)研究無法基于共同標(biāo)準(zhǔn)進行，而對于特定行為界定的模糊進一步導(dǎo)致對其結(jié)果無法比較，嚴(yán)重影響了對于黑頸鶴行為學(xué)研究的進展。

基于此，本文通過對于黑頸鶴的野外觀察來完成黑頸鶴個體行為的描述及行為譜的繪制，旨在提出黑頸鶴的個體行為分類體系，以為更深層次的黑頸鶴行為研究提供基礎(chǔ)。

1 研究方法

1.1 野外工作及數(shù)據(jù)采集

在越冬地，野外工作分別在2012年1月、2013年3月、2014年3月開展于云南昭通大山包和貴州威寧草海，在繁殖地分別在2013年4～6月、2014年4～7月開展于甘肅、青海、四川以及西藏的黑頸鶴繁殖棲息地。野外工作中，除直接觀察外，同時使用攝影攝像設(shè)備(Canon 7D & Canon 400 mm F5.6)來對黑頸鶴的行為進行記錄。最終，共獲得有效視頻文件約8 930 min，有效照片63 200余張。基于以上材料，本文對黑頸鶴在野外條件下的個體行為進行分類、描述，并在Adobe Illustrator CC當(dāng)中完成行為譜的繪制。

1.2 行為分類系統(tǒng)及術(shù)語

在對黑頸鶴的個體行為進行分類時，主要參考由Ellis et al.(1991)提出并由Masatomi(2004)完善的鶴類個體行為分類體系，其為鶴類個體行為提供了一套科學(xué)的、標(biāo)準(zhǔn)化的框架[3-4]；在對行為進行描述時，主要參考Masatomi and Kitagawa(1975)，其以丹頂鶴(Grusjaponensis)為例對鶴類行為描述中提供了一套基于形態(tài)學(xué)特征的準(zhǔn)則[9]。本研究中新記錄到的行為在命名時基于Ellis et al.(1991)提出的命名法[3]，并在文中以下劃線標(biāo)出。對于部分行為(出現(xiàn)次數(shù)n<100)，除完成行為的描述和行為譜的繪制外，還對其發(fā)生的次數(shù)和持續(xù)的時間加以統(tǒng)計，而頻繁出現(xiàn)的行為(n≥100)則不做統(tǒng)計[4]。為減少不必要的誤解，本行為譜中所列行為均為在野外有過觀察和記錄的，對于其他列入Ellis et al.(1991)、Masatomi(2004)行為分類系統(tǒng)但于黑頸鶴上尚未在野外觀察到且未見報道的行為不予記錄[3-4]。

2 結(jié)果與分析

基于靜息姿態(tài)，黑頸鶴的個體行為可以被劃分為：Ⅰ.休憩行為，Ⅱ.感知行為，Ⅲ.保養(yǎng)行為，Ⅳ.運動行為，Ⅴ.攝食、排遺和排泄。

SP-靜息姿態(tài)Still PosturesSP-A.雙足站立Stand(圖 1-1.)

雙腿直立支撐身體。長時間站立時，兩腿常平行；若為行進中暫停，雙腿則或交叉。

SP-B.單足站立One-leg-stand(圖 1-2.)

身體由一腿支撐，另一腿或收回腹部，或貼合腹部，或自然懸垂。當(dāng)個體采單腿站立時，為保持重心，支撐腿略向外傾斜。

SP-C.臥姿Lie(圖 1-3.)

雙腿折疊于軀干下。在越冬地覓食后的下午，黑頸鶴常以此方式在草地上進行休息，而在繁殖地僅有1次記錄(非孵化)。

Ⅰ-休憩行為Sleep-related BehaviorⅠ-A.探頭休憩Head-forward-sleep(圖 1-2.)

軀干水平，頸部收縮，頭部自然指向前方，喙部微向下指，雙眼閉合(n>100)。

Ⅰ-B.垂頭休憩Head-droop-sleep(圖 1-1.)

類似于探頭休憩，但頭部自然下垂，頜部倚靠在頸部進行休息(n>100)。

Ⅰ-C.倚背休憩Head-lean-sleep(圖 1-4.)

軀干略后傾，兩翼微微上抬，頸部由一側(cè)向后彎曲，頭部前伸倚靠在背部進行休息(n>100)。

Ⅰ-D.藏頭休憩Head-tuck-sleep(圖 1-3.)

類似倚背休憩，但喙部插入背部覆羽當(dāng)中。在觀察中發(fā)現(xiàn)，眼睛雖然閉合但始終暴露在外，一旦出現(xiàn)干擾，其眼睛會迅速睜開，并抽出頭部進行警戒(n>100)。

圖1 靜息姿態(tài)，休憩行為以及感知行為Fig.1 Still posture，sleep-related behavior and sensory-related behavior

Ⅱ-感知行為Sensory-related BehaviorⅡ-A.觀察Observe

往往同黑頸鶴其他行為同時進行，抑或構(gòu)成其其他行為序列的部分。例如，覓食過程中搜尋食物，行進或飛行過程中察看前方的情況等。在進行觀察時，個體往往較放松，表現(xiàn)為體羽不蓬松，頭部裸皮不充血(n>100)。

Ⅱ-B.警戒Vigilance

在警戒時，由于干擾的存在，個體往往較為緊張，表現(xiàn)為體羽蓬松，頭部裸皮充血，步態(tài)局促等。警戒行為的程度可以很好地通過頭頸部的動作來進行表征。

Ⅱ-B-1.低態(tài)雙目凝視Binocular-gaze-low(圖 1-5.)

軀干水平，頸部向上，頭部指向干擾來源，此時頸部仍較彎曲(n>100)。

Ⅱ-B-2.中態(tài)雙目凝視Binocular-gaze-mid(圖 1-6.)

軀干略后傾，頸部上抬但仍然彎曲(n>100)。

Ⅱ-B-3.高態(tài)雙目凝視Binocular-gaze-high(圖 1-7.)

軀干后傾，頸部極度伸直，頭頂裸皮完全張開，注視干擾來源，之后往往緊隨以踱步、鳴叫等行為(n>100)。

Ⅲ-保養(yǎng)行為Maintenance BehaviorⅢ-A.體表保養(yǎng)Care of body surfaceⅢ-A-1.理羽Preen

理羽是由一系列旨在清潔羽毛上黏附的異物、去除體表的寄生蟲、分開糾結(jié)纏繞的羽枝、理順羽毛的方向和促進羽毛的更換等行為構(gòu)成。理羽行為可出現(xiàn)在3種靜息姿勢下，且會因清潔身體不同部分的需要而以不同的形態(tài)表達，部分典型理羽行為見圖 2-12～21。按照梳理羽毛的動作，理羽行為可以分作：

Ⅲ-A-1.1.嚙咬Nibble(圖 2-8.)

喙插入羽毛著生部，小幅開合，快速嚙咬羽毛根部及附近表皮。在此過程中，喙的嚙咬由一個部位迅速轉(zhuǎn)移至與其相鄰的另一個部位，不作大幅劃動(n>100)。

Ⅲ-A-1.2.挑出Winkle(圖 2-9.)

常見于雪夜后的清晨，其目的在于分開糾結(jié)纏繞在一起的羽毛。喙部深插入體羽(特別是背部覆羽中)，而后自體表迅速向外挑出，挑出幅度由所打理羽毛的長度決定，往往止于羽端，但因慣性會多劃出一段距離。挑出的方向則是由受處理羽區(qū)羽毛的著生方向和身體——尤其是頭頸的生理結(jié)構(gòu)來共同決定(n>100)。

圖2 保養(yǎng)行為(Ⅲ-A-1～3)Fig.2 Maintenance behavior(Ⅲ-A-1～3)

Ⅲ-A-1.3.梳理Comb-out(圖 2-10.)

常見于清洗身體后個體對初級飛羽及尾羽的清理中。喙部輕咬住尾羽或初級飛羽根部自羽根沿羽干向外捋動，以除去蓄積在羽毛中的水分或懸墜于飛羽端部的冰塊——對于后者而言，喙部開合的幅度恰小于冰塊的寬度而大于羽毛的厚度(n>100)。

Ⅲ-A-1.4.熨平Stroke(圖 2-11.)

頸部彎向一側(cè)，以頭部裸皮壓向體表，隨后邊揮動喙部邊將頭部在整個背部往復(fù)碾動掃動。此行為目的在于壓平被風(fēng)吹起的羽毛(n>100)。

Ⅲ-A-2.涂油Oil(圖 2-22.)

頭部由體側(cè)探向體后，該側(cè)翼同時輕垂，喙部探向尾脂腺，同時尾亦轉(zhuǎn)向同側(cè)接近。喙部撥開尾脂腺上方的羽毛后在腺體上滑動，通過圓形摩擦運動使得頭側(cè)亦沾滿油脂。隨后，通過上述不同的理羽行為，個體將尾脂涂滿全身(n=19)。

Ⅲ-A-3.摩擦頭部Head-rub(圖 2-23)

類似于理羽行為中的熨平，但頭部僅在翕部及肩部碾動摩擦，喙部亦出離體羽，旨在解除頭頂裸皮瘙癢(～4.98 s，n=6)。

Ⅲ-A-4.抓撓Scratch(圖 3-24.)

該行為可分為頭部抓撓(Head-scratch)和頸部抓撓(Neck-scratch)[4]，但二者常相繼發(fā)生。單足或雙足站立，軀干略后傾，頸部斜向下指，頭部直伸。一側(cè)腿抬起，以中趾抓撓頭頸，期間頭頸亦轉(zhuǎn)動以配合足趾抓撓(～7.93 s，n=22)。其后往往緊隨以擺頭或俯身抻頸抖動的行為。

Ⅲ-A-5.嚙咬表皮Nibble-integuments

李筑眉等(2005)首先在黑頸鶴上報道[29]，基于嚙咬部位的不同可分為：

圖3 保養(yǎng)行為(Ⅲ-A-4～8)Fig.3 Maintenance behavior(Ⅲ-A-4～8)

Ⅲ-A-5.1.檢足Nibble-foot(圖 3-25.)

雙足站立，頸部下彎，頭部向下，喙部探向足趾進行嚙咬(n=11)。

Ⅲ-A-5.2.嚙咬脛跗部Nibble-leg(圖 3-26.)

類似前者，但俯身嚙咬脛跗部(n=8)。

Ⅲ-A-6.俯身啄除Dangle-leg-care

單足站立，軀干保持水平，頭頸由足趾抬起一側(cè)后彎，以去除附著在跗蹠部的異物，如冰塊、黏土等，持續(xù)時間因附著物不同而異。

Ⅲ-A-6.1.探喙啄咬Dangle-leg-bite(圖 3-27.)

通過喙部對異物進行咬啄(n=5)。

Ⅲ-A-6.2.咬緊擺足Bite-leg-swing(圖 3-28.)

喙端咬緊附著物之后，該側(cè)腿向后緩慢蹬踹(n=1)。

Ⅲ-A-6.3.擺足撞喙Dangle-leg-strike(圖 3-29.)

頭頸固定，抬起的跗蹠部向前擺動，使其上的凝著物反復(fù)撞擊喙部(n=1)。

Ⅲ-A-7.加溫融化Thaw(圖 3-30.)

見于越冬地的黑頸鶴處理凝結(jié)在其跗蹠部的鐲狀冰塊。單腿站立，期間亦會表現(xiàn)有理羽等行為，但腿部幾乎完全為腹部覆羽所覆蓋以為其加溫。在野外觀察中即記錄到：黑頸鶴在反復(fù)頓足、啄咬無效后將其收于腹下，一段時間后再度啄咬，如此往復(fù)共加溫7 min 20 s，最終將其去除(n=1)。

Ⅲ-A-8.滑行蹭足Glide-foot-rub(圖 3-31.)

動作類似于垂腿飛行。雙腿垂下，污染腿保持靜止，另一腿反復(fù)屈伸、上下，以進行摩擦及拍打。見于在飛行中黑頸鶴除去黏在足趾間的大塊泥巴(n=1)。

Ⅲ-A-9.清洗身體Bathe

在黑頸鶴清洗身體過程中共記錄到5種行為，其有可能單獨或組合出現(xiàn)：

Ⅲ-A-9.1.洗涮喙部Bill-slosh(圖 4-32.)

雙足站立，軀干略前傾，頭頸近乎垂直扎入水面，喙部入水即上揚。頭部在揚起時或揚起后快速橫向甩動，持續(xù)約0.74 s(n=24)。

Ⅲ-A-9.2.濯洗頭部Head-neck-dip(圖 4-33.)

雙足站立，軀干輕微或極度前傾(取決于其站于水中或岸邊)，頸部快速直伸下擺，頭部垂直入水，之后立即快速旋轉(zhuǎn)抬起，有時反復(fù)多次(～2.69 s，n=21)。

Ⅲ-A-9.3.蜷翅擊水Wing-thrash(圖 4-34.)

腿部彎曲身體浮于水中，兩翼部分打開并反復(fù)劇烈拍擊水面，同時軀干后部及尾亦劇烈起伏(～2.52 s，n=13)。

Ⅲ-A-9.4.傾體揚水Roll-slosh(圖 4-35.)

腿部彎曲身體浸于水中，一腿斜向后上方揚出水面，同時軀干向?qū)?cè)扭轉(zhuǎn)約45°，頭頸就勢浸入水中(～2.24 s，n=8)。

Ⅲ-A-9.5.頭頸揚水Belly-slosh(圖 4-36.)

軀干前傾使胸部浸入水中，頭頸迅速下壓，喙部直擊水面，入水后頭部隨即轉(zhuǎn)向一側(cè)揚出，以將水撩至背部(～3.55 s，n=11)。

圖4 保養(yǎng)行為(Ⅲ-A-9～10)Fig.4 Maintenance behavior(Ⅲ-A-9～10)

Ⅲ-A-10.潤濕頭部Head-immerse(圖 4-37.)

雙足站立，頸部向下擺動，頭部慢速垂直插入水中至完全濕潤——以此區(qū)別于洗漱喙部；頭部入水后，頸部即行上擺，頭部保持垂直角度脫離水體——以此區(qū)別于飲水行為；期間未見有任何甩動頭頸動作——以此區(qū)別于濯洗頭部；頸部上揚至頭部脫離水體后復(fù)向下插入，反復(fù)多次，喙部指向同一位置——以此區(qū)別于水中俯身啄刺。僅在繁殖期蚊蟲密布的覓食地記錄到1次(n=1)，在記錄到的視頻影像中可清晰地分辨出鏡頭前大群蚊蟲似煙霧狀，據(jù)此推測黑頸鶴意在藉由水流驅(qū)避蚊蟲，解除搔癢，保護不覆羽的頭部裸皮。

Ⅲ-A-11.垂翼Wing-droop

雙足站立，一側(cè)翼或兩側(cè)翼初級飛羽垂下，僅見于洗澡后晾干飛羽(n=2)。

Ⅲ-B.抖動ShakeⅢ-B-1.甩喙Bill-flick

類似于洗漱喙部，但喙并不沾濕，僅通過甩動去除喙部黏附污物(～0.27 s，n=43)。

Ⅲ-B-2.擺頭Head-shake(圖 5-38.)

雙足站立，頸部向上，頭部橫向快速反復(fù)甩動(～0.56 s，n=36)。

圖5 保養(yǎng)行為(Ⅲ-B-2～11)Fig.5 Maintenance behavior(Ⅲ-B-2～11)

Ⅲ-B-3.俯身抻頸抖動Ruffle-shake(圖 5-39.)

雙足站立，軀干略前傾，兩翼輕離軀干，頸部首先稍作收縮而后迅速向斜下旋轉(zhuǎn)刺出(～1.50 s，n=29)。

Ⅲ-B-4.鉤頸抖動Ruffle-bow-up(圖 5-40.)

雙足站立，頸部向上直伸，頭部向下鉤回，喙部貼壓頜下覆羽。軀干快速抖動，同時兩翼及尾羽明顯出離軀干(～2.53 s，n=17)。

Ⅲ-B-5.俯身抖頸Ruffle-bow-down(圖 5-41.)

雙足站立，軀干前傾，頸部彎曲而貼合軀干，兩翼向外部分打開，快速抖動，其間可見羽毛明顯蓬起(～2.78 s，n=3)。

Ⅲ-B-6.抖動兩翼Wing-shake(圖 5-42.)

雙足站立，軀干略后傾而頸部略彎曲，兩翼快速抖動并輪流拍打身體(～1.24 s，n=31)。其后常緊隨以俯身抻頸抖動或提翅。

Ⅲ-B-7.提翅Wing-fold

常作為降落、抖動或伸展后的調(diào)整動作出現(xiàn)，也見于覓食過程的行走中。兩翼初級飛羽幾乎同時上提并自然貼合軀干(～0.19 s，n=57)。

Ⅲ-B-8.擺尾Tail-wag(圖 5-43.)

雙足站立，軀干前傾，三級飛羽微微聳起，露出短小的尾羽。尾羽首先伸張，繼而快速左右擺動(～1.03 s，n=69)。

Ⅲ-B-9.甩足Leg-flick(圖 5-44.)

單足站立，軀干略前傾，懸垂腿脛跗部向后緊貼腹部，跗蹠部反復(fù)向后作蹬踹動作(～2.76 s，n=33)。

Ⅲ-B-10.頓足Leg-stomp(圖 5-45.)

見于跗蹠部凝著有較大冰塊或其足趾部黏帶有成塊的泥巴。類似于甩足，但跗蹠部迅速垂直下擺將足爪砸向地面，反復(fù)多次，直到附著物脫落后才停止(～3.21 s，n=11)。若頓足行為無法使附著物脫落，便會出現(xiàn)俯身啄除行為。

Ⅲ-B-11.仰身振翅Rise-flap(圖 5-46.)

雙足站立，頸部極度向上，雙翼同時向外張開并向上舉，到達極限位置后用力向前扇動。約3.41 s(n=26)后，頭頸下降復(fù)位，兩翼收回。一般作為去除冰雪或清潔身體后殘留的水分的動作出現(xiàn)，亦見于飛離夜棲地前的準(zhǔn)備動作。

Ⅲ-C.伸展StretchⅢ-C-1.哈欠Yawn(圖 6-47.)

軀干水平，頸部直伸，喙部張開至30°角左右，并在30°～35°角之間反復(fù)開合，頭部同時左右輕擺。約5.52 s(n=18)后喙閉合，眨眼，動作完成。

Ⅲ-C-2.單腿伸展One-leg-stretch(圖 6-48.)

軀干前傾，頸部略向后屈，一腿向后緩慢蹬出，至跗蹠部同脛跗部夾角約為135°時保持，進而繼續(xù)緩慢后蹬至腿完全伸直；保持此姿勢，軀干繼續(xù)前傾(～15.60 s，n=25)。

Ⅲ-C-3.單腿單翼伸展Side-stretch(圖 6-49.)

類似單腿伸展，但同側(cè)翼向外同時伸出呈弓形。腿翼至最大幅度后保持，持續(xù)約10.66 s(n=21)。

Ⅲ-C-4.單腿兩翼伸展Two-wing-spread-stretch(圖 6-50.)

類似單腿伸展，但兩側(cè)翼向外同時伸出至最大幅度后保持(～9.87 s，n=20)。

Ⅲ-C-5.俯身張翅Bow-stretch(圖 6-51.)

類似于俯身抖頸，但兩翼動作不同且詭異——身體前傾，兩翼上舉至次級飛羽著生部豎直后，初級飛羽著生部向外完全打開，并在水平方向反復(fù)開合(～5.98 s，n=6)。

圖6 保養(yǎng)行為(Ⅲ-C-1～5)Fig.6 Maintenance behavior(Ⅲ-C-1～5)

Ⅳ-運動行為LocomotoryⅣ-A.行走AmbulatoryⅣ-A-1.俯身行走Walk-neck-low(圖 7-52.)

軀干前傾，頸部略屈曲向下而喙部指向地面。常見于覓食過程當(dāng)中，個體常慢速走動而目光左右掃視食物(n>100)。

Ⅳ-A-2.正常行走Walk-neck-mid(圖 7-53.)

軀干基本水平，頸部略彎曲，頭部略向下指(n>100)。

Ⅳ-A-3.挺身行走Walk-neck-high(圖 7-54.)

類似正常行走，但軀干略后傾，頭頸極度向上，頭部基本水平向前(n>100)。

Ⅳ-A-4.高步行走Walk-high-step(圖 7-55.)

頸部彎曲而頭部向前，軀干極度前傾以將腹部抬離水面。常見于在水中行走時(n>100)。

圖7 運動行為(Ⅳ-A-1～6)Fig.7 Locomotory(Ⅳ-A-1～6)

Ⅳ-A-5.緩步慎行Walk-low-step(圖 7-56.)

僅見于個體慢速通過冰面。類似于正常行走，但羽毛蓬起且兩翼略抬高，步幅小，速度慢，且后足抬起后足趾幾不收攏即向前邁出(n>100)。

Ⅳ-A-6.張翅助行Walk-wing-open(圖 7-57.)

僅見于個體快速通過冰面。軀干后傾而頭頸前伸，步伐極大，同時兩翼上舉并扇動以保持平衡(n>100)。

Ⅳ-B.奔跑Run

個體形態(tài)類似于俯身行走，正常行走或挺身行走，但步頻顯著高于行走(n>100)。

Ⅳ-C.跨步Stride(圖 8-58.)

見于個體在跨過溝坎或越過障礙物時。頭頸向上，兩翼上舉同時扇動，一足蹬地跨過障礙，另一足向腹部收回復(fù)向前探出(n>100)。

Ⅳ-D.跳躍Leap

雙足站立，頸部屈曲，軀干明顯前傾；雙腿彎曲并向下蹬地，兩翼同時打開(罕見扇動)，隨后垂直跳離地面(n>100)。

圖8 運動行為(Ⅳ-C～E-1.2)Fig.8 Locomotory(Ⅳ-C～E-1.2)

Ⅳ-E.飛行FlightⅣ-E-1.起飛TakeoffⅣ-E-1.1.助跑起飛Run-flap(圖 8-59.)

個體起飛采取的最常見方式。雙足站立，軀干首先極度前傾，頭頸向上直伸，頸部略向后弓出，保持該姿勢(“預(yù)飛行姿勢”，表達強烈的起飛信號[8])；隨后頸部向前擺出，軀干水平，向前跨步；同時兩翼向外水平伸出并快速扇動，約3.21 s(n=41)后雙腿抬離地面。

Ⅳ-E-1.2.跳躍起飛Spring-up(圖 8-60.)

類似跳躍，但兩翼打開后猛烈扇動，隨后轉(zhuǎn)向，扇翅順風(fēng)向飛離(～0.71 s，n=41)。常見于助跑距離不足或迎強風(fēng)站立時。

Ⅳ-E-2.飛行及滑翔Flap & GlideⅣ-E-2.1.伸腿飛行Leg-straight(圖 9-61.)

頭頸平伸，雙腿向后直伸且足爪合攏，頭頸、軀干及腿爪幾呈直線(n>100)。

Ⅳ-E-2.2.收腿飛行Leg-tuck(圖 9-62.)

類似伸腿飛行，但雙腿折疊回收于腹下(n=16)[26]。

Ⅳ-E-2.3.滑行Parachute(圖 9-63.)

軀干水平或略后傾，頸部略揚起，頭部有時揚起有時環(huán)顧左右，兩翼水平張開(少見扇動)，雙腿自然下垂(n=5)。

Ⅳ-E-2.4.垂腿飛行Leg-dangle-glide(圖 9-64.)

類似滑行，但飛行時頸部直伸向前(n>100)。

Ⅳ-E-2.5.扇翅飛越Trunk-incline-flap(圖 9-65.)

身體傾斜約同地面呈45°，頸部水平伸出，雙腿自然屈曲下垂，兩翼快速扇動(n>100)。見于短距離飛越河流或溝谷，亦作為洗澡后去除身體水分的動作出現(xiàn)。

Ⅳ-E-3.降落Alight(圖 9-66.)

兩翼向外水平伸出，雙腿自然下垂，尾羽完全打開，頸及軀干由水平挺向豎起以減速，期間頭部始終指向著陸點；接觸地面瞬間，腿部斜向下蹬出，足趾張開，雙足同時著陸，隨后向前邁出，期間兩翼完全張開輔助減速(n>100)。若短距離飛行或著陸點空間狹促，著陸時兩翼不停扇動以快速減速。

圖9 運動行為(Ⅳ-E-2.1～F)Fig.9 Locomotory(Ⅳ-E-2.1～F)

Ⅳ-F.游泳Swim(圖 9-67.)

僅在繁殖地有過一次記錄(n=1)。兩翼向上抬起(仍保持收回狀)，尾羽同時聳起，個體浮于水中雙腿輪流滑水，姿勢笨拙，速度緩慢。

Ⅴ-攝食、排遺和排泄Ingestion，EgestionandExcretion

Ⅴ-A.覓食ForagingⅤ-A-1.俯身抓啃Nibble(圖 10-68.)

雙足站立，軀干前傾，頸部彎曲，喙部幾乎垂直插入地表約1/4喙長的深度。上下喙快速小幅開合，用以嚙咬土塊。常見于個體翻掘埋于地下的土豆等食物時(n>100)。

Ⅴ-A-2.撥動搜尋Flick(圖 10-69.)

雙足站立，頸部彎曲，喙部插入土壤或貼靠被移動的物體；頭部橫向扭動，使用喙端來移動物體。常見于個體撥開土壤或牦牛的干糞等物體以尋找隱藏昆蟲時(n>100)。

Ⅴ-A-3.劃水搜捕Stab(圖 10-70.)

雙足站立，軀干前傾，頸部近乎直伸，喙部張開完全沒入水中，但雙眼一般暴露在水面外；軀干扭轉(zhuǎn)，頭部以同水面約呈45°的角度在水中大幅劃動。常見于個體搜捕水中的魚時(n>100)。

Ⅴ-A-4.屈頸琢取Peck(圖 10-71～73.)

雙足站立，頸部首先收縮，隨后喙部輕開并迅速向外刺向食物。除常見于黑頸鶴啄食地表食物外，亦見其啄食灌木上的冰凌，捕捉網(wǎng)圍欄上的蜘蛛，草甸上的鼠兔及蜥蜴等，身體姿態(tài)隨食物位置不同而有差異(n>100)。

Ⅴ-A-5.咬緊拾起B(yǎng)ite(圖 10-74.)

姿態(tài)近似張嘴抓啃，但喙部開合角度更大，咬合更有力，隨后頸部抬升，軀干隨之水平。常見于個體從地面拾起土豆或從水中叼起魚等較大體積食物時(n>100)。

Ⅴ-A-6.咬緊拖拽Thrash(圖 10-75.)

雙足站立，軀干前傾，喙部緊咬食物而頸部收屈，隨后身體以足為軸心猛烈向上(后)拖拽食物，直至其離開地面。常見于個體拔拽植物的地下部分時(n>100)。

Ⅴ-A-7.拋投震蕩Cast(圖 10-76.)

雙足站立，軀干前傾，喙部緊咬食物，頭部擺動將其拋出。常見于個體將捕捉到的魚甩扔上岸，或震蕩黏附在土豆等植物地下部分食物上的泥土?xí)r(n>100)。

Ⅴ-A-8.轉(zhuǎn)移食物Carry(圖 10-77.)

喙部緊咬食物，采用俯身行走或正常行走將食物轉(zhuǎn)移(n>100)。

圖10 攝食、排遺和排泄(Ⅴ-A)Fig.10 Ingestion，egestion and excretion(Ⅴ-A)

Ⅴ-A-9.俯身啄刺Probe(圖 10-78.)

雙足站立，軀干前傾而頸部屈曲，喙部合攏并反復(fù)迅速刺向食物(19 s內(nèi)記錄到31次)。若食物卡在喙部，則常通過甩動頭部將其去除。常見于個體殺死捕捉到的魚時，但在野外過程中亦記錄一個體喙部卡有大塊土豆，據(jù)此推測其或通過此方式來穿刺以分裂大塊食物。

Ⅴ-A-10.涮洗食物Swill(圖 10-79.)

姿態(tài)近似拋投震蕩，但喙部緊咬食物并反復(fù)按入水中，同時頭部左右擺動以涮洗食物。常見于個體在水中清洗由泥水中獲得的草本植物時(n=3)。

Ⅴ-B.吞咽SwallowingⅤ-B-1.俯身抽咽Toss-swallow(圖 11-80.)

最常見的吞咽食物的方式，常見于個體吞咽進食小塊食物時。頸部首先伸出，喙部咬緊食物，隨后頸部快速收屈而后急停，喙部同時輕開，食物就慣性落入口中(n>100)。

Ⅴ-B-2.挺身吞咽Neck-pumping(圖 11-81.)

常見于個體吞咽大塊食物時，如魚等。雙足站立，軀干略后傾而頸部收屈，喙微張而后迅速向斜上伸出，直伸后咬緊食物收屈，反復(fù)多次，直到完成吞咽。吞咽完成后往往見上下喙快速小幅開合以為調(diào)整——似咂嘴——有時亦伴有眨眼(n>100)。

Ⅴ-B-3.飲水Drink or Scoop-swallow(圖 11-82.)

雙足站立，雙腿微屈，軀干首先極度前傾，喙部微張插入水中，身體繼續(xù)前傾，頸部向后彎曲，以使得水流入喙中；隨后軀干上擺，頭部揚起抬離水面，至軀干水平后頭部上揚使水流入腹中，期間喙部保持微張直至飲水完成后才見閉合(～4.05 s，n=57)。

Ⅴ-C.嘔吐Vomit

僅見于一次遠距離野外觀察，極類似于Masatomi(2004)對于白頭鶴(Grusmonacha)嘔吐行為的描述，分作擺喙(Bill-shake)，張口(Gape)以及嘔吐(Vomit)3個動作[4](n=1)。

圖11 攝食、排遺和排泄(Ⅴ-B～D)Fig.11 Ingestion，egestion and excretion(Ⅴ-B～D)

Ⅴ-D.排便Defecate(圖 11-83.)

雙腿站立，頸部略彎曲，軀干略前傾同時兩翼及尾輕抬高，排便。動作完成后軀干恢復(fù)水平，兩翼及尾降下，常伴隨以提翅及擺動尾部。亦見于飛行過程中，彼時個體往往滑行或采伸腿飛行姿勢(n>100)。

3 討論

以往對于鶴類個體行為的研究已經(jīng)為當(dāng)前對于鶴類個體行為的討論奠定了牢固的基礎(chǔ)[3-4]，但時至今日仍有許多問題難以厘清。由于鶴類個體行為的連續(xù)性及其靈活性，個體行為的固定分類框架在面對具有多種功能的行為時常難以適用，進而導(dǎo)致了在分類體系中行為重復(fù)及混淆的出現(xiàn)。因此，基于野外觀察中獲得的材料，我們在此對黑頸鶴個體行為分類體系中的一些問題展開討論。

依據(jù)行為的動機，Ellis et al.(1991)將鶴類的個體行為分為如下8個類別：1)孵化行為(Hatching)，2)姿勢(Posture)，3)休憩行為(Sleep-related behavior)，4)感知行為(Sensory-related behavior)，5)保養(yǎng)行為(Maintenance behavior)，6)體溫調(diào)節(jié)及呼吸(Thermoregulatory and respiratory)，7)運動行為(Locomotory)以及8)攝食、排遺和排泄(Ingestion，egestion and excretion)(以下簡稱“Ellis系統(tǒng)”)[3]。隨后，從行為形態(tài)的角度出發(fā)，其進一步將每一大類細分作不同的級別和條目[3]。而在此分類體系中，“鳴叫”(Vocalizations)以及“其他涉及種內(nèi)及種間關(guān)系的行為”被排除在外[3]。而正是基于這樣的考慮，本文將“孵化行為”亦從該分類體系中去除。原因在于，作為黑頸鶴繁殖期最為關(guān)鍵的階段，孵化并非一個獨立發(fā)生的動作，反而，其是基于親鳥與其后代間存在的種內(nèi)相互關(guān)系而出現(xiàn)的?；诖耍覀儍A向于認為孵化行為從屬于繁殖行為，進而應(yīng)歸類至繁殖行為(社會行為)的范疇當(dāng)中。其次，個體的姿勢在絕大部分情況下均是作為其他個體或社會行為的組成或表現(xiàn)而存在，而該行為本身并不具有如“站立”或“臥下”的動機，因此不應(yīng)與后續(xù)按照行為動機分類的行為并列。誠然，對于姿勢的描述可以極大地便利對于其他個體行為的討論，因此在本文中，僅移除了“姿勢”一類前可能導(dǎo)致困惑和混淆的編號，并將其更名為更準(zhǔn)確的“靜息姿態(tài)”。

休憩行為(Ⅰ)同之前的認知相比具有更高的多樣性。以眼睛長時間閉合作為標(biāo)準(zhǔn)，我們增補了一類新的行為，即倚背休憩(Ⅰ-C)。反而，本文將“藏頭觀察”(Head-tuck-watch)從該分類中移除，原因在于這一觀察環(huán)境的動作多出現(xiàn)于個體休息前后，因而應(yīng)屬于感知行為的范疇。

基于對行為發(fā)生動機的考量，本文將感知行為(Ⅱ)重新劃分為觀察(Ⅱ-A)和警戒(Ⅱ-B)兩類，而外界刺激是區(qū)別以上兩類行為的唯一標(biāo)準(zhǔn)。換言之，外界刺激的存在與否直接決定了個體對于外界的感知是被動亦或主動。本文認為，個體對于外界環(huán)境或其他物體的主動感知即是觀察，而作為對于外界刺激的響應(yīng)而出現(xiàn)的對刺激的感知則為警戒。此外，觀察幾乎存在于黑頸鶴所有個體以及社會行為當(dāng)中——只要雙眼睜開，個體即處于觀察這一狀態(tài)當(dāng)中。Ellis系統(tǒng)將個體的警戒行為分為3類，即低態(tài)雙目凝視(Ⅱ-B-1)，中態(tài)雙目凝視(Ⅱ-B-2)以及高態(tài)雙目凝視(Ⅱ-B-3)[3]，本文極為贊同。而且，無論個體采站姿、臥姿或何種姿態(tài)，以上3種行為均可以極為準(zhǔn)確地表征個體的警戒程度，且同樣適用于其他鶴類(如白頭鶴等)。同時，不可否認的是，警戒行為常具有更多的社會性內(nèi)涵，但考慮個體行為分類體系的完整性，在此仍將其作為個體行為譜的一部分呈現(xiàn)。此外，本文認為Ellis系統(tǒng)中的“眨眼”(Blink)或“單眼凝視”(Monocular-gaze)作為感知的動作方式而非具體的行為或姿態(tài)，應(yīng)當(dāng)從該行為分類體系中移除。

保養(yǎng)行為(Ⅲ)是鶴類個體行為中最為復(fù)雜的部分，原因即在于單個動作或行為常具有極其豐富的功能和含義。相較于Ellis系統(tǒng)[3]，首先，本文移除了“舒適行為”(Comfort Behavior)這一類別，并將其下行為按照動作發(fā)生的形態(tài)進行了細分和重組。原因在于，舒適行為這一類目過多地強調(diào)了行為發(fā)生的動機是“舒適身體而非清潔”，然而對于某些行為來說以上動機在實際情況當(dāng)中往往是極其微妙，難以區(qū)分的。例如，抖動行為(Ⅲ-B)可以起到舒適身體和蓬松羽毛的作用，但其同時亦具備將體表附著的污物移除的功能?；诖耍覀儗⒈ｐB(yǎng)行為分為3大類別，即體表保養(yǎng)(Ⅲ-A)，抖動(Ⅲ-B)以及伸展(Ⅲ-C)，并移除了原分類框架當(dāng)中“其他舒適行為”(Other Comfort Behavior)這一含糊的說辭。在體表保養(yǎng)(Ⅲ-A)當(dāng)中，我們?nèi)コ恕芭钏珊晚樆?Fluff and sleek)這一行為，因為其實際上是抖動身體所帶來的必然結(jié)果。考慮到解除瘙癢這一相同動機，我們將摩擦頭部(Ⅲ-A-3)同抓撓(Ⅲ-A-4)置于一處。此外，在這一分類中本文進行了諸多增補——如俯身啄除(Ⅲ-A-6)和加溫融化(Ⅲ-A-7)見于個體去除附著在其脛跗部的冰塊，滑行蹭足(Ⅲ-A-8)見于個體由黏土地飛離后(亦見于灰鶴Grusgrus)，潤濕頭部(Ⅲ-A-10)僅在繁殖地有過1次記錄，而本文猜測其可能是個體抵御蚊蟲、解除瘙癢的一種方式。在抖動(Ⅲ-B)當(dāng)中，由于動作的相似性，我們將甩喙(Ⅲ-B-1)、甩足(Ⅲ-B-9)以及仰身振翅(Ⅲ-B-11)均移至此處。在野外觀察中發(fā)現(xiàn)，黑頸鶴對于附著在其喙部及脛跗部的污物極其介意，往往停下其正在進行的覓食并不惜花費大量時間對其處理。頓足(Ⅲ-B-10)在本文中首次得到記錄，其常見于黑頸鶴于黏土地中覓食時(n=11)，推測其可能由甩足行為衍生而來。此外，提翅(Ⅲ-B-7，n=57)以及擺尾(Ⅲ-B-8，n=69)通常作為理羽、抖動或伸展之后的整理動作出現(xiàn)，因此在整理行為中具有較高的出現(xiàn)頻率。在伸展(Ⅲ-C)中，除去哈欠(Ⅲ-C-1)與俯身張翼(Ⅲ-C-5)，其他3種行為出現(xiàn)頻率相近(n=25/21/20)，原因在于其常作為一完整的行為序列依次出現(xiàn)。與之類似，蜷翅擊水(Ⅲ-A-9.3)，傾體揚水(Ⅲ-A-9.4)以及頭頸揚水(Ⅲ-A-9.5)亦常作為清洗身體的行為序列而記錄到相近的出現(xiàn)頻次(n=13/8/11)。

我們移除了Ellis系統(tǒng)中“體溫調(diào)節(jié)以及呼吸”這一行為類別[3]，原因在于其中行為常作為其他行為的組成部分(如“蓬松和順滑體羽”)，或明顯作為其他行為表達的結(jié)果而出現(xiàn)(如“頭頂裸皮的收縮與舒張”)。

在運動行為(Ⅳ)當(dāng)中，基于對運動過程中身體姿態(tài)的考慮，我們對行走(Ⅳ-A)進行了重新分類。其中，緩步慎行(Ⅳ-A-5)和張翅助行(Ⅳ-A-6)作為黑頸鶴以不同速度通過冰面的兩類行為被新記錄到，而跨步(Ⅳ-C)作為黑頸鶴翻越障礙物的一種行為被新添入其個體行為譜中。Ellis系統(tǒng)中存在“行為過渡動作”(“Transitional action patterns”)這一概念[3]，但本文認為其列舉的該范疇內(nèi)的許多動作均屬于某些特定行為而鮮見獨立表達，因而在此并不采納該類目，并將其下動作歸回其從屬的行為序列。依據(jù)飛行的時間順序，我們將飛行過程中的行為進行了重新組合與分類，即起飛(Ⅳ-E-1)，飛行及滑翔(Ⅳ-E-2)以及降落(Ⅳ-E-3)。此外，在野外觀察中發(fā)現(xiàn)，收腿飛行(Ⅳ-E-2.2)常見于越冬地及遷徙停歇地的寒冷清晨，因而在此附議Kong et al.(2016)認為該行為為黑頸鶴在飛行時溫暖腿部的方式的觀點[26]。此外，在先前的野外工作當(dāng)中亦在類似環(huán)境條件下于黑頸鶴同屬其他物種中有過記錄，如白頭鶴、丹頂鶴以及灰鶴等。

在攝食、排遺和排泄(Ⅴ)當(dāng)中，本文基于“搜尋食物——獲得食物——處理食物”的邏輯順序?qū)σ捠承袨檫M行了重新整理。先前Ellis et al.(1991)在其行為譜中列有“喙部撥動”(Bill-flick)，“喙部推開”(Bill-push-open)以及“喙部側(cè)推”(Bill-side-push)3種行為[3]，然而在野外觀察中注意到以上3種常作為黑頸鶴處理地下埋藏食物的3種動作而混雜出現(xiàn)，難以區(qū)分。因此，本文贊同Masatomi(2004)的觀點[4]，將其合為撥動搜尋(Ⅴ-A-2)一類?！皵[喙”(Bill-shake)，“張口”(Gape)以及“嘔吐”(Vomit)在野外僅見于黑頸鶴試圖將食物吐出，因此我們將其同歸為嘔吐(Ⅴ-C)一類。此外，同預(yù)飛行姿勢相類似，排便(Ⅴ-D)亦常作為某些情況下個體準(zhǔn)備逃離的動機而表達。

本文新近增補的許多新的行為均記錄于特殊的環(huán)境條件下：挑出(Ⅲ-A-1.2)、俯身啄除(Ⅲ-A-6)以及加溫融化(Ⅲ-A-7)均記錄于降大雪后，滑行蹭足(Ⅲ-A-8)與頓足(Ⅲ-B-10)均記錄于個體于黏土地覓食后，而緩步慎行(Ⅳ-A-5)以及張翅助行(Ⅳ-A-6)均記錄于個體在通過結(jié)冰水面時。以上行為在沒有相應(yīng)特殊條件時均未有記錄。

作為基于野外觀察數(shù)據(jù)的黑頸鶴個體行為研究的階段性總結(jié)，本文在對材料處理時仍難以逃離許多難以決斷的問題，諸如：個體行為通常作為連貫的序列出現(xiàn)，而固定的分類體系及框架常常難以對一些動作或功能較為模糊的行為做出明確的區(qū)分；同時，個體本身在面對不同的環(huán)境條件時會主動地對行為發(fā)生的動作、持續(xù)時間以及先后次序等屬性進行調(diào)整，甚至在一常見的固定行為序列中添加新的動作以滿足實際需求。因此，究竟應(yīng)以何種標(biāo)準(zhǔn)用于個體行為的分類？如何對分類體系和框架進行調(diào)整才可能無重復(fù)無遺漏地對行為進行整理？以上困惑或貫穿于整個鶴類行為研究的始終，但可以確定的是隨著基礎(chǔ)的行為學(xué)工作的不斷積累與討論，這些問題必將逐漸明朗清晰。

致謝：感謝何芬奇老師與劉小龍老師在行為描述上給出的建議。感謝李苞、溫立嘉在外業(yè)數(shù)據(jù)收集上給予的幫助，感謝于鳳琴女士、楊杰才讓、花青加、智華喇嘛、扎西桑俄堪布以及董江天女士在野外工作中給予的幫助。

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[25] 鄺粉良，倉決卓瑪，李建川，等.藏北黑頸鶴孵卵期的晝間時間分配和行為節(jié)律[J].楚雄師范學(xué)院學(xué)報，2015，30(6)：22-25，41.[Kuang Fenliang，Cangjue Zhuoma，Li Jianchuan，et al.Diurnal time budget and behavior rhythm ofGrusnigricollisduring incubating phase in northern tibeten[J].Journal of Chuxiong Normal University，2015，30(6)：22-25，41.]

[26] Kong Dejun，Li Fengshan，Liu Qiang，et al.Flight of black-necked cranes(Grusnigricollis)with legs drawn up：behavioral responses to low temperature and duration of exposure[J].The Wilson Journal of Ornithology，2016，128(1)：144-149.

[27] Lu Guangyi，Wang Rongxing，Ma Lirong，et al.Characteristics of dry upland roosts of the black-necked crane(Grusnigricollis)wintering in Yongshan，China[J].The Wilson Journal of Ornithology，2017，129(2)：323-330.

[28] 車燁，楊樂，李忠秋.西藏拉薩越冬黑頸鶴家庭群的警戒同步性[J].生態(tài)學(xué)報，2018，38(4)：1-7.[Che Ye，Yang Le，Li Zhongqiu.Vigilance synchronization of wintering black-necked crane(Grusnigricollis)families in Tibet[J].Acta Ecologica Sinica，2018，38(4)：1-7.]

[29] 李筑眉，李鳳山.黑頸鶴研究[M].上海：上海科技教育出版社，2005.[Li Zhumei，Li Fengshan.Research on the black-necked crane[M].Shanghai：Shanghai Scientific and Technological Education Publishing House，2005.]

As one of the inherent characteristics of birds，various behaviors are displayed to fulfil their needs of survival[1].Based on various motivations，bird behaviors can be recognized and classified as individual(non-social)or social behavior，and between which the individual behaviors are the most crucial components and the elementary units of all avian behaviors[2].However，under some circumstances，the social meaning expressed by recognized individual behaviors may obscure the division between social and individual behaviors[3]，resulting in serious difficulties for both academic and practical work.Therefore，it is necessary to establish an elaborate ethogram of individual behaviors as a fundamental tool for further study of complete behavior sequences，social behaviors and abstruse behavioral mechanisms[4].

Gruiformes is an ancient group of avian species[5]，many meaningful efforts have been made in their ethological study[6-10].As an endemic species on the Tibetan Plateau，the Black-necked CraneGrusnigricollisrepresents a unique evolutionary branch that adapts to the alpine environment[11-12].In the ethological study on the Black-necked Crane，reported work basically focused on the fundamental behavior and associated time budget[13-28]；while its individual behaviors，especially its classification and categorization，have not been well explored，and limited attempts were made merely based on captive individuals[3，17].The lack of the unification in recognition and classification of the non-social behaviors of the Black-necked Crane greatly weakens the credibility of its further ethological study，which are commonly based on various vague and coarse categories，leading to great difficulties in the comprehension and comparison of these researches.

Consequently，based on the field observation and associated video materials，we made elaborate descriptions and illustration for the individual behavior of the Black-necked Crane.We aim that this work could provide a complete individual behavior compendium for the Black-necked Crane，in order to pave a safe way for further ethological study on this unique crane lineage.

1 Methods

1.1 Fieldwork and Data Collection

Breeding observation occurred in April-June 2013 and April-July 2014 in Gansu，Qinghai，and Sichuan Province and the Tibet Autonomous Region，China，basically covering all the known populations of the Black-necked Crane.During fieldwork，besides direct observation in the wild，video cameras were used to record the Black-necked Crane’s ethon.Finally，we obtained ～63 200 effective images and approximately 8 930-minute-long of effective video records in total.Based on these materials，we categorized，described，and illustrated the individual(non-social)behaviors(ethons)of the Black-necked Crane，and then finished the ethogram in Adobe Illustrator CC.

1.2 Framework and Terminology

We generally followed the compendium put forward by Ellis et al.(1991)and supplemented by Masatomi(2004)as the framework for categorizing the crane’s ethons，which proposed a detailed framework of individual(non-social)behaviors for crane family[3-4]；the description of the behaviors was according to the work of Masatomi and Kitagawa(1975)on the Red-crowned CraneGrusjaponensis，which presented a set of complete and accurate principles for describing crane individual behaviors[9].New supplemental ethons were named following the nomenclature of Ellis et al.(1991)and underlined[3].For a more intuitive understanding of Black-necked Cranes’ behavior，frequency and duration of uncommon quantifiable ethons(n<100)were counted[4].To avoid possible confusions，here we only involve those ethons that have been recorded in our own field work，or has been reported by previous studies on this species[3-4].

2 Results

Based on the elementary Still Postures，the Black-necked Crane’s individual behavior could be categorized as：Ⅰ.Sleep-related Behavior，Ⅱ.Sensory-related Behavior，Ⅲ.Maintenance Behavior，Ⅳ.Locomotory，Ⅴ.Ingestion，Egestion and Excretion.

Still PosturesSP-A.Stand(Fig.1-1.)

The crane stands on both feet.Legs are usually kept parallel，but may be in tandem in a transitory stand during movements.

SP-B.One-leg-stand(Fig.1-2.)

The crane’s body is supported by one leg，while the other is tucked or dangled.

SP-C.Lie(Fig.1-3.)

Both legs are folded beneath the trunk.On a warm afternoon in the wintering grounds，Black-necked Cranes were commonly observed resting in this posture，but only a single record was made in the breeding grounds(not hatching).

Ⅰ.Sleep-related BehaviorⅠ-A.Head-forward-sleep(Fig.1-2.)

With the trunk held horizontally and the neck retracted fairly，the crane rests with its head kept low(n>100).

Ⅰ-B.Head-droop-sleep(Fig.1-1.)

Similar to Head-forward-sleep，but the head is kept lowest，with bill pointing steeply down to the ground(n>100).

Ⅰ-C.Head-lean-sleep(Fig.1-4.)

The trunk held horizontally and both wings folded faintly up，the crane bends its neck backward and leans its head on the back(n>100).

Ⅰ-D.Head-tuck-sleep(Fig.1-3.)

Similar to Head-lean-sleep，but the bill is kept obliquely down and is tucked into the dorsal feathers(n>100).

Ⅱ.Sensory-related BehaviorⅡ-A.Observe

This ethon were observed to occur with or as a part of other behaviors，such as seeking food or watching forward during movement，etc.During observing，the crane is usually relaxed with feathers sleeked and crown contracted(n>100).

Ⅱ-B.Vigilance

During vigilance，the crane behaves nervously to disturbances，with feathers fluffed and crown expanded.The degree of the vigilance could be accurately identified by the form of neck.

Ⅱ-B-1.Binocular-gaze-low(Fig.1-5.)

With trunk kept horizontally or slightly down，the crane gazes with its neck retracted fairly(n>100).

Ⅱ-B-2.Binocular-gaze-mid(Fig.1-6.)

Lifting the trunk slightly up，the crane gazes with its neck retracted slightly(n>100).

Ⅱ-B-3.Binocular-gaze-high(Fig.1-7.)

With the trunk held obliquely down，the crane gazes with its neck extremely stretched and the crown expanded(n>100).

Ⅲ.Maintenance BehaviorⅢ-A.Care of body surfaceⅢ-A-1.Preen

Preen is a comprehensive matrix of a series of ethons for removing foreign matter and parasites from the body surface，separating tangled feathers，promoting molting，etc.It occurs in all postures of the crane and could transform to cater different needs for various body parts.Part of typical ethons of preening were shown in Fig.2-12 to Fig.2-21.According to the subtle differences in the movements，preening could be categorized as：

Ⅲ-A-1.1.Nibble(Fig.2-8.)

Inserting the bill deeply into the feathers，the crane slightly opens and closes the bill，rapidly nibbling the base parts of feathers and body surface(n>100).

Ⅲ-A-1.2.Winkle(Fig.2-9.)

Frequently occurred after snowy nights，the crane inserts the bill deeply into its trunk feathers(dorsal coverts especially)，then winkles out rapidly to tease apart tangled feathers(n>100).

Ⅲ-A-1.3.Comb-out(Fig.2-10.)

Tenderly biting the base of the primaries or rectrices，the crane slides its bill from the base to tip slowly，eliminating the water or hanging ice from long feathers-for the latter situation，the opening amplitude of the bill is exactly smaller than the size of the ice，but loose for the feather(n>100).

Ⅲ-A-1.4.Stroke(Fig.2-11.)

With the neck bent backward to one side，the crane presses its crown on the back，and then strikes the head with the bill swung，in order to sleek the windblown feathers on the back(n>100).

Ⅲ-A-2.Oil(Fig.2-22.)

Bending the head backward and slightly drooping one wing，the crane directs the bill to the uropygial gland，with the rectrices turned to the same side.The bill pushes aside the feathers above the gland，and then the crane daubs the oil on the bill and head through sliding movements.Via various preening movements，the crane smears this oil on the body(n=19).

Ⅲ-A-3.Head-rub(Fig.2-23.)

Similar to Stroke，but the head only rubs the mental parts and the scapular feathers，to relieve the itching of bare cap(～4.98 s，n=6).

Ⅲ-A-4.Scratch(Fig.3-24.)

This ethon could be divided into Head-scratch and Neck-scratch[4].Standing on one or both feet，with the trunk inclined obliquely down and the neck entirely stretched，the crane lifts one leg to scratch the head or the neck with the nail of the middle toe.The neck rotates slowly to cater to the scratching of the toe，usually followed by Head-shake or Ruffle-shake(～7.93 s，n=22).

Ⅲ-A-5.Nibble-integuments

Reported by Li(2005)in the Black-necked Crane for the first time[29]，two ethons were specified based on the body parts nibbled：

Ⅲ-A-5.1.Nibble-foot(Fig.3-25.)

Standing in tandem，with the neck retracted slightly downwards，the crane nibbles its foot integuments(n=11).

Ⅲ-A-5.2.Nibble-leg(Fig.3-26.)

The crane nibbles the tarsus integuments(n=8).

Ⅲ-A-6.Dangle-leg-care

Standing on one foot with the trunk kept horizontal，the crane bends its neck to remove foreign matter(e.g.，large ice)from the dangling foot.Three ethons were observed and will be displayed solely or grouped at will：

Ⅲ-A-6.1.Dangle-leg-bite(Fig.3-27.)

The crane bites the object repeatedly(n=5).

Ⅲ-A-6.2.Bite-leg-swing(Fig.3-28.)

The crane clenches the object and swings the dangling leg backward to tear the object from the foot(n=1).

Ⅲ-A-6.3.Dangle-leg-strike(Fig.3-29.)

The crane holds the head in a fixed position and lifts the dangling leg horizontally，and then swings the leg forward to strike the object to the bill repeatedly(n=1).

Ⅲ-A-7.Thaw(Fig.3-30.)

Only observed on the wintering grounds when a Black-necked Crane was trying to melt a large “ice fetter” fixed in one tarsus(n=1).In this case，after repeated Dangle-leg-care and Leg-stomp，the crane stood on one foot and tucked the foot under belly coverts for 7 min 20 s and finally removed it.

Ⅲ-A-8.Glide-foot-rub(Fig.3-31.)

Similar to Leg-dangle-glide，but both feet repeatedly rub and hit each other to remove a large lump of slime(n=1).

A-9.Bathe

Five ethons were recorded during bath，and which may be displayed solely or grouped freely during the whole bathing course：

Ⅲ-A-9.1.Bill-slosh(Fig.4-32.)

Standing on both feet，with the trunk inclined slightly down and the neck fairly retracted，the crane dips its bill into the water vertically(only the bill became wet during this ethon)，and then lifts up with rapid flicks(～0.74 s，n=24).

Ⅲ-A-9.2.Head-neck-dip(Fig.4-33.)

Standing on both feet，with the trunk inclined slightly or obliquely down(depending on whether the crane was standing on the bank or in the water)，the crane dips the head into the water，and then rises up immediately with fast rotations(～2.69 s，n=21).

Ⅲ-A-9.3.Wing-thrash(Fig.4-34.)

With legs bent to “float” on the water，both wings open partially to sides and repeatedly thrash the water surface，and the tail hits the water simultaneously(～2.52 s，n=13).

Ⅲ-A-9.4.Roll-slosh(Fig.4-35.)

Floating on the water，one leg strikes water upward to rotate the trunk to ～45° with the water surface alternatively(“wobbled”)，with the opposite wing obliquely folded to side for balance，and the head and neck dip into the water simultaneously(～2.24 s，n=8).

Ⅲ-A-9.5.Belly-slosh(Fig.4-36.)

The crane hits the breast into the water with the bill pointed steeply up，then head lifts immediately with the bill turned to one side to splash water backwards(～3.55 s，n=11).

Ⅲ-A-10.Head-immerse(Fig.4-37.)

Standing on both feet，the crane dips the head into the water slowly and vertically(different from Bill-slosh).After the head is fully immersed，the neck rises at a moderate speed without any rotation or other lateral movement(different from Drink and Head-neck-dip).During the repetition of this ethon，the bill always points to the same place in the water(different from foraging in water).This ethon was only observed once in the breeding area(n=1)，when many mosquitos flew around，indicating that its purpose may be to protect the bare cap from bites and to relieve itching with water.

Ⅲ-A-11.Wing-droop

Standing on both feet，the crane droops one or both primaries.This ethon was only observed after bathe as a method of drying feathers(n=2).

Ⅲ-B.ShakeⅢ-B-1.Bill-flick

Similar to Bill-slosh，but this ethon is aimed at eliminating foreign matter from the tip of the bill(～0.27 s，n=43).

Ⅲ-B-2.Head-shake(Fig.5-38.)

Standing on both feet，with the trunk inclined obliquely down and the neck stretched，the head shakes rapidly(～0.56 s，n=36).

Ⅲ-B-3.Ruffle-shake(Fig.5-39.)

Standing on both feet，with the trunk inclined slightly down and the neck retracted slightly，and both wings lifted slightly from the trunk，Black-necked Crane stabs the head downward with fast rotations(～1.50 s，n=29).

Ⅲ-B-4.Ruffle-bow-up(Fig.5-40.)

Standing on both feet，with the trunk kept horizontal and the neck stretched，and the bill pressing body，the crane rapidly shakes the body with wings and tail obliquely elevated(～2.53 s，n=17).

Ⅲ-B-5.Ruffle-bow-down(Fig.5-41.)

Standing on both feet，with the trunk inclined obliquely down and neck retracted fairly，and with both wings opened partially to sides，the crane rapidly shakes its body with feathers extremely fluffed(～2.78 s，n=3).

Ⅲ-B-6.Wing-shake(Fig.5-42.)

Standing on two feet，with the trunk inclined slightly up and the neck retracted slightly，the crane shakes and pats both wings rapidly.This ethon was usually followed by Ruffle-shake and Wing-fold(～1.24 s，n=31).

Ⅲ-B-7.Wing-fold

This ethon usually occurred as an adjustment movement after shaking，stretching and alight，and was also observed during walking or foraging.Both primaries elevate and pat the trunk slightly(～0.19 s，n=57).

Ⅲ-B-8.Tail-wag(Fig.5-43.)

Standing on both feet，with the trunk inclined obliquely or slightly down，the crane elevates both tertiaries to expose the fully fanned rectrices，and usually followed by a rapid horizontal shake(～1.03 s，n=69)

Ⅲ-B-9.Leg-flick(Fig.5-44.)

Standing on one foot，with the trunk slightly inclined down，the crane dangles one leg and swings the tarsus rapidly(～2.76 s，n=33).

Ⅲ-B-10.Leg-stomp(Fig.5-45.)

This was observed when large ice or clay was sticking to the crane’s foot.Similar to Leg-flick，but the tarsus stomps on the ground rapidly and forcefully(～3.21 s，n=11).This behavior would not terminate until the foreign matter is removed，and Dangle-leg-care may occur subsequently if this ethon does not work.

Ⅲ-B-11.Rise-flap(Fig.5-46.)

Standing on both feet，with the trunk inclined upright and the neck stretched，the crane holds both wings widely to sides，and then flaps violently.After ～3.41 s(n=26)，the crane lowers head and folds both wings back.The purpose of this behavior could be removing snow or water from its wings，or acting as a preparation movement before leaving the roosting area.

Ⅲ-C.StretchⅢ-C-1.Yawn(Fig.6-47.)

With the trunk inclined slightly up and the neck stretched，the crane repeatedly opens and closes its bill within an amplitude between 30°-35°，and the head turns around simultaneously.After ～5.52 s(n=18)，the bill closes and usually is followed by slow blinks.

Ⅲ-C-2.One-leg-stretch(Fig.6-48.)

With the trunk inclined slightly down and the neck retracted fairly，the crane swings one leg backward slowly；the leg is held still when the angle of the tibia and tarsus reached ～135°，and then continues to swing until fully stretched.Holding this posture，the crane inclines its trunk down(～15.60 s，n=25).

Ⅲ-C-3.Side-stretch(Fig.6-49.)

Similar to One-leg-stretch，but the wing of the same side opens widely to side，and the leg doesn’t suspend and hold during stretching.The wing and the leg are fixed after fully stretched for ～10.66 s(n=21).

Ⅲ-C-4.Two-wing-spread-stretch(Fig.6-50.)

Similar to Side-stretch，but both wings open widely to sides(～9.87 s，n=20).

Ⅲ-C-5.Bow-stretch(Fig.6-51.)

Similar to Ruffle-bow-down，but the movement of the wings is performed oddly.Both secondaries elevate vertically and the primaries repeatedly open and close horizontally(～5.98 s，n=6).

Ⅳ.LocomotoryⅣ-A.AmbulatoryⅣ-A-1.Walk-neck-low(Fig.7-52.)

This ethon was commonly observed while searching for food during foraging.With the trunk inclined slightly down，the neck retracted slightly and the bill directed to the ground，the crane walks at a rather low speed，sometimes with eyes scanning the ground ahead(n>100).

Ⅳ-A-2.Walk-neck-mid(Fig.7-53.)

With the trunk basically kept horizontal and the neck retracted fairly，the crane walks at a moderate speed(n>100).

Ⅳ-A-3.Walk-neck-high(Fig.7-54.)

Similar to Walk-neck-mid，but the head is elevated and kept forward，with the neck retracted slightly(n>100).

Ⅳ-A-4.Walk-high-step(Fig.7-55.)

Occurred when Black-necked Crane was walking in the water.With the neck retracted fairly and the head kept forward，the crane walks with the trunk obliquely inclined downward to elevate its belly above the water(n>100).

Ⅳ-A-5.Walk-low-step(Fig.7-56.)

Only observed when Black-necked Crane was passing glacial surfaces.Similar to Walk-neck-mid，but with body feathers fluffed and both wings folded faintly up，the crane steps forward with a small stride length(n>100).

Ⅳ-A-6.Walk-wing-open(Fig.7-57.)

Occurred when Black-necked Crane was passing glacial surfaces.With the trunk inclined backward and both wings opened widely upwards for balance，the crane flapped and walked with a large stride length(n>100).

Ⅳ-B.Run

Similar to the Walk-neck-low，Walk-neck-mid or Walk-neck-high，but the stepping frequency of Run is obviously higher than walking(n>100).

Ⅳ-C.Stride(Fig.8-58.)

Occurred when Black-necked Crane passed through gaps or obstacles in its way.With the head elevated first and both wings opened widely upwards and flapped simultaneously，the crane pushes the ground with one leg and elevates the other to stride over the obstacle(n>100).

Ⅳ-D.Leap

Standing on both feet with the neck retracted fairly，the trunk inclined obliquely down，the crane first bends both legs，and then pushes down on the ground，with the wings opened widely to sides simultaneously，and then jumps vertically off the ground(n>100).

Ⅳ-E.FlightⅣ-E-1.TakeoffⅣ-E-1.1.Run-flap(Fig.8-59.)

The most common way for Black-necked Crane to take off.Standing on both feet，with trunk inclined obliquely up and the neck stretched vertically and slightly arched，the crane keeps the posture called “Preflight Posture”[8]，expressing a strong signal of taking off.Then with neck lowered and trunk inclined horizontally，the crane steps forward with a large stride length.At the same time，both wings open widely upwards and flap rapidly with both feet leaving the ground after ～3.21 s(n=41).

Ⅳ-E-1.2.Spring-up(Fig.8-60.)

Usually observed when the runway was short or the wind was strong.The crane springs upwards，both wings flap constantly and then open horizontally to sides for gliding(～0.71s，n=41).

Ⅳ-E-2.Flap & GlideⅣ-E-2.1.Leg-straight(Fig.9-61.)

With the neck stretched horizontally forward，the legs backward and the claws closed，the crane flaps or glides with the body in a nearly straight line(n>100).

Ⅳ-E-2.2 Leg-tuck(Fig.9-62.)

Similar to Leg-straight，but both legs are tucked into the belly feathers for warming bare feet[26](n=16).

Ⅳ-E-2.3.Parachute(Fig.9-63.)

The crane glides(infrequent flapping)with its trunk kept horizontal or slightly inclined backward，neck stretched up，and both legs dangling(n=5).

Ⅳ-E-2.4.Leg-dangle-glide(Fig.9-64.)

Similar to Parachute，but the crane stretches its neck forward while gliding(n>100).

Ⅳ-E-2.5.Trunk-incline-flap(Fig.9-65.)

With the trunk inclined obliquely up(at the angle of ～45°)and the neck stretched horizontally，the crane flaps constantly with both legs bent and dangling(n>100).This was observed during short-distance flight，or occurred as one of the methods to dry the feathers after bathing.

Ⅳ-E-3.Alight(Fig.9-66.)

With both wings stretched out horizontally and legs dangling，the crane erects its trunk and opened the rectrices to slow down(n>100).While landing，the crane lands with both feet first and then steps forward with wings opened widely to sides.When after a short-distance flight or the landing distance is short，the crane would constantly flap its wings for a rapid deceleration.

Ⅳ-F.Swim(Fig.9-67.)

This was only observed once in the breeding area(n=1).With both wings and rectrices lifted，the crane strikes the water alternately with its feet.

Ⅴ.Ingestion，Egestion and ExcretionⅤ-A.ForagingⅤ-A-1.Nibble(Fig.10-68.)

With the neck retracted downward and a quarter of the bill inserted into the soil，the crane opens and closes the bill rapidly with a small amplitude，biting at the clods for insidious potatoes or invertebrates(n>100).

Ⅴ-A-2.Flick(Fig.10-69.)

With the neck retracted downward，the crane inserts and pushes the bill into the soil or presses on various objects，to uncover food beneath(n>100).

Ⅴ-A-3.Stab(Fig.10-70.)

With the trunk inclined forward and the neck stretched down，the crane turns the trunk to dip and stab the opened bill into the water at an angle of ～45°.Occurred when the crane was trying to catch fish in the water(n>100).

Ⅴ-A-4.Peck(Fig.10-71～73.)

Retracting the neck first，the crane stabs the bill towards food rapidly，which was always followed by Toss-Swallow.In addition to pecking objects on the ground，we also recorded the crane pecking icicles on a shrub，spiders on a fence，etc.，and the postures varied with the object pecked(n>100).

Ⅴ-A-5.Bite(Fig.10-74.)

Similar to Nibble，but the bill closes more powerfully with a larger amplitude.Occurred when the crane lifted objects such as potatoes or fish from the ground or water(n>100).

Ⅴ-A-6.Thrash(Fig.10-75.)

Standing on both legs，with the trunk inclined forward and the neck retracted downward，the crane bites an object firmly and repeatedly tugged it off the ground(n>100).

Ⅴ-A-7.Cast(Fig.10-76.)

The crane bites an object and swings the head to cast it out.Occurred in situations such as casting fish to the bank and tossing dirt off the potatoes(n>100).

Ⅴ-A-8.Carry(Fig.10-77.)

Biting an object firmly，the crane transfers food during Walk-neck-low or Walk-neck-mid(n>100).

Ⅴ-A-9.Probe(Fig.10-78.)

Standing on two legs，with the trunk inclined forward and the neck retracted downward，the crane probes the closed bill into food violently(31 times in 19 s).If the food stuck on its bill，the crane would use Head-shake to remove it.Usually，this occurred when the crane was killing a captive fish，but we also recorded a Black-necked Crane having a piece of a potato stuck on its bill，which may indicate that the crane could use this ethon to crack and separate large food.

Ⅴ-A-10.Swill(Fig.10-79.)

Similar to Cast，the crane holds grass and repeatedly immerses and flicks it in water for cleaning food(n=3).

Ⅴ-B.SwallowingⅤ-B-1.Toss-swallow(Fig.11-80.)

The most common ethon used to swallow food.Stretching the neck downward and biting the food，the crane retracts the neck rapidly，and then suddenly stops with the bill opened to swallow food by inertance(n>100).

Ⅴ-B-2.Neck-pumping(Fig.11-81.)

Standing on both feet，with the trunk slightly inclined backward and the neck retracted，the crane stabs rapidly，and then retracts the neck with the food held by the bill，repeating after swallow finished(n>100).Occurred especially when a Black-necked Crane was swallowing large food(e.g.，fish).

Ⅴ-B-3.Drink or Scoop-swallow(Fig.11-82.)

Standing on both legs with the trunk slightly inclined forward and the legs obliquely bent，the crane faintly opens the bill and immerses it in water，and then the bill turns horizontally to fill the mouth with water.Finally，the crane lifts and stretches up the neck with bill slightly opened(～4.05 s，n=57).

Ⅴ-C.Vomit

Only observed one time from a long distance away.The behavior was in highly accordance with the description and illustration by Masatomi on the Hooded CraneGrusmonacha(2004)[4]，and included three ethons：bill-shake，gape and vomit(n=1).

Ⅴ-D.Defecate(Fig.11-83.)

Standing on both legs，with the neck slightly retracted，the crane inclines forward and lifts both wings and tail slightly.The trunk lays back after defecating is finished，and sometimes followed by Wing-fold or Tail-wag.This was also observed during flight，in which case the crane usually glided with Leg-straight(n>100).

3 Disscussion

Previous studies have paved the way for current studies on the individual behavior of the crane species[3，4]，but until now some issues still remained controversial.Due to continuity and flexibility of the individual(non-social)behaviors，the factitious classification of their behaviors sometimes showed relatively poor applicability in categorizing those multi-functional ethons，leading to repetition and confusion in behavioral classifications.Therefore，based on field observations of the Black-necked Crane，we added to discussions about the individual behaviors of the crane species with this compendium.

According to the behavioral motivations，the repertoire of Ellis et al.(1991)categorized the cranes’ individual behaviors into eight classes，as follows：1)Hatching，2)Posture，3)Sleep-related behavior，4)Sensory-related behavior，5)Maintenance behavior，6)Thermoregulatory and respiratory，7)Locomotory and 8)Ingestion，egestion and excretion[3].Subsequently，from a morphological view，they subdivided these classes into various divisions and sections[3].In this case，vocalizations and “all other ethons relating to both inter-and intra-specific social interactions” were excluded[3].However，here we are inclined to omit I.Hatching from this framework under the same consideration.As one of the most crucial periods during the breeding season，hatching is not a single ethon that is performed alone，but is instead based on the intraspecific relationship among both parents and their immature offspring，which should not be considered as an inanimate object.Hence，we categorized hatching as part of breeding behavior，and then considered it to be a social behavior.Still postures are mostly displayed as the components of other individual or social behaviors，and listing them as a separate group could greatly simplify the repertoire to a great degree.Yet to omit the possible confusion caused by the continuous serial number ahead，we suggest that this item should to be discriminated against following behavior classes.Consequently，we removed the serial number ahead of this item，and more accurately listed it as “Still Posture”(to exclude postures that occur during flight，e.g.Leg-straight，Leg-tuck，etc.).

Sleep-related-behavior(Ⅰ)is a more diverse group than our previous recognition.Taking the closing of the eyelids as the standard，we specified one supplementary ethons-Head-lean-sleep(Ⅰ-C).On the contrary，Head-tuck-watch was omitted from this class because this sensory-related ethon is more likely to be the crane’s observation before or after sleep.

Sensory-related-behavior(Ⅱ)was reintegrated according to the motivation，and was divided into Observe(Ⅱ-A)and Vigilance(Ⅱ-B).The presence of external stimulation determines the crane’s motivation；in other words，the detection is active or passive.The active perception of the environment and other objects or individuals is considered to be Observe，while the passive detection to the environment，as a response to stimulation，is considered to be Vigilance.Observe is part of almost all the behaviors of the crane；as long as the eyelids open，observation will occur.As for Vigilance，three ethons listed by Ellis et al.(1991)，Binocular-gaze-low(Ⅱ-B-1)，Binocular-gaze-mid(Ⅱ-B-2)and Binocular-gaze-high(Ⅱ-B-3)[3]，could be used to accurately estimate the degree of vigilance，even when the crane is lying or in other postures，which would also be applicable in other crane species(e.g.，Hooded Crane).Undeniably，Vigilance may express some social meaning，but considering it helps present a more complete and reasonable repertoire，we still included it in this ethogram.Moreover，Blink and Monocular-gaze，performed as sensory actions(instead of exact ethons or postures)，were removed from this ethogram.

Maintenance behavior(Ⅲ)is the most complicated part of the crane’s individual behaviors，which attributes to the multiple functions expressed by some single ethons.Compared to Ellis et al.(1991)[3]，at first，we omitted the saying of “comfort behavior，” then briefly classified and named them according to the body form.This simplification is because the item inappropriately gave excessive emphasis to “the behaviors for comforting but not for cleaning，” yet these functions are too complicated and subtle to be separated and elucidated.For example，Shake(Ⅲ-B)could be used to comfort the body and fluff the feathers，but also to remove foreign matters from the body surface.Hence，we divided the Maintenance behavior into three sections，Care of body surface(Ⅲ-A)，Shake(Ⅲ-B)and Stretch(Ⅲ-C)，and we omitted the ambiguous term “other comfort behavior.”

In the Care of body surface(Ⅲ-A)，we omitted Fluff and sleek because it usually emerged as the result of shaking the body.Considering the same motivation of relieving itching，we moved Head-rub(Ⅲ-A-3)together with Scratch(Ⅲ-A-4).Moreover，many new ethons were recorded for the first time：Dangle-leg-care(Ⅲ-A-6)and Thaw(Ⅲ-A-7)were observed to remove large ice from the tarsus；Glide-foot-rub(Ⅲ-A-8)was recorded after the crane took off from the clayed ground，which was also found in the sympatric Common CraneGrusgrus；Head-immerse(Ⅲ-A-10)was only observed once in the breeding ground，and we thought it could be a strategy of the crane to protect its bare cap from mosquitos.

In Shake(Ⅲ-B)，due to the similarity in the movements，we moved in the Bill-flick(Ⅲ-B-1)，Leg-flick(Ⅲ-B-9)and Rise-flap(Ⅲ-B-11).In the field observations，we noticed that the Black-necked Crane was sensitive to foreign matter on their bill and legs，and this was confirmed with the frequency of these ethons’ occurrence.Leg-stomp(Ⅲ-B-10)was first recorded after a crane was foraging in the clayed ground(n=11)，and we thought it was derived from the Leg-flick.Wing-fold(Ⅲ-B-7，n=57)and Tail-wag(Ⅲ-B-8，n=69)were always performed as an adjustment after preening，shaking and stretching，which showed high occurrence frequencies.In Stretch(Ⅲ-C)，except for Yawn(Ⅲ-C-1)and Bow-stretch(Ⅲ-C-5)，the frequencies of the other three ethons were close(n=25/21/20)，always been performed in sequence.Similarly，Wing-thrash(Ⅲ-A-9.3)，Roll-slosh(Ⅲ-A-9.4)and Belly-slosh(Ⅲ-A-9.5)were also performed as a successive bathing sequence，showing a close occurrence frequency(n=13/8/11).

We omitted “Thermoregulatory and respiratory” in Ellis’s compendium[3]，because the ethons it contains were mostly performed as parts of other behaviors(e.g.，F(xiàn)luff and Sleek)or were apparent in the change of body features during the display of other ethons(e.g.，Crown-contraction or Crown-expansion).

In Locomotory(Ⅳ)，according to the body form while moving，we reclassified Ambulatory(Ⅳ-A).Walk-low-step(Ⅳ-A-5)and Walk-wing-open(Ⅳ-A-6)were recorded as two separate ethons used when passing through the glacial surface，corresponding to different velocities.Stride(Ⅳ-C)was recorded as a new ethon when the crane passed through obstacles or gaps in its way，where the height that the legs were lifted varied with the object size.Ellis et al.(1991)proposed the class of “Transitional action patterns，” but most of these ethons belong to some constant behavior sequences with poor flexibility；thus，we omitted this category and moved these ethons back to their respective behavior sequences.Based on the time sequence of flying，we regrouped and sorted ethons in Flight into three sections，Takeoff(Ⅳ-E-1)，F(xiàn)light(Ⅳ-E-2)and Alight(Ⅳ-E-3).Besides，according to our fieldwork，Leg-tuck(Ⅳ-E-2.2)was rather common on cold mornings in the wintering grounds and stopover sites，we therefore infer that this ethon as one strategy of the black-necked crane to warm bare foot during flight，which was in accordance with Kong et al.(2016)[26].Moreover，during our previous fieldwork，this ethon was also frequently observed other inter-specific individuals，such as Hooded，Red-crowned and Common cranes under similar circumstances.

In Ingestion，Egestion and Excretion(Ⅴ)，we sorted the ethons in Foraging according to the time sequence of “searching food-obtaining food-processing food” for the convenience of future supplements.Bill-flick，Bill-push-open and Bill-side-push were listed in the repertoire of Ellis et al.(1991)[3].However，from the practical field observations，these three ethons were always performed as a complex matrix，and their subtle differences were simply reflected in amplitude and direction of the bill.Hence，as mentioned by Masatomi(2004)，it may be more appropriate to combine them into Flick(Ⅴ-A-2)[4].Bill-shake，Gape and Vomit were unique and only occurred when the crane intended to spit food from its mouth，so we integrated them into Vomit(Ⅴ-C).Similar to Preflight posture，Defecate(Ⅴ-D)also indicated a strong signal of escape in some situations.

Many of the new ethons were observed in special environmental conditions，such as Winkle(Ⅲ-A-1.2)，Dangle-leg-care(Ⅲ-A-6)and Thaw(Ⅲ-A-7)were observed during or after snowy weather；Glide-foot-rub(Ⅲ-A-8)and Leg-stomp(Ⅲ-B-10)were observed after foraging in the clayed ground；Walk-low-step(Ⅳ-A-5)and Walk-wing-open(Ⅳ-A-6)were observed when passing through the glacial surface.Not a single record of these ethons were made without those particular conditions.

As a temporary summary of the individual behaviors of the Black-necked Crane from field observations，we are still faced with many intractable issues，such as the following：behaviors are usually performed on a flexible continuum，so rigid categories have work poorly in clearly distinguishing ambiguous ethons；according to the practical situation the crane confronts，it will adjust the ethon and the actions’ amplitude，frequency，etc.，and possibly add new ethons in fixed behavior sequences to cater to different needs.Hence，what standard should we use to identify and to demarcate these behavioral acts？How can we improve the framework so that we can categorize these ethons without repetition or omission？The questions above may remain through the whole course of ethological study on the crane species，but they will certainly become clearer with the continuous accumulation and discussion of fundamental ethological work.

Acknowledgements

We appreciate He Fenqi，Liu Xiaolong for their advice on the behavior descriptions.We acknowledge Li Bao and Wen Lijia for their contributions in the field observation，and we thank Fengqin Yu，Yangchieh Ts’aijang，Huach’ing Chia，and Lama Chihhua，Kanbo Tashi Sangpo，and Jiangtian Dong for their support in the fieldwork.