正確地使用鳥音回播來賞鳥 (初稿版)
The Proper Use of Playback in Birding (last edited April 7th, 2011)
David Sibley – Sibley Guides
整理翻譯 by張珮文 Peiwen Chang
近年來隨著錄音及播放器材的數位化與快速進展，在野外使用回播（playback：播放鳥類的聲音）吸引鳥類出現來賞鳥的情況大幅增長。這也使得鳥友們在野外利用回播來賞鳥的相關倫理問題受到了重視與爭論。
With the recent surge in the availability of digital audio devices, the use of playback to attract birds into view has increased exponentially. This has fueled an ongoing debate among birders about the ethical issues surrounding the use of recorded bird songs in the field.
無庸置疑的，使用回播鳥音來賞鳥是一個非常有用的工具，而每個鳥友也都會掙扎於是否使用此項工具。我們可以利用鳥音的回播使許多害羞的鳥種可以出現在比較明顯的地方，但我們不是那麼的確定這行為對於鳥類是否有嚴重的影響，而許多的爭論重點都在於在道德上應不應該使用回播。在此篇文章我假設回播是可以被使用的，而將重點放在對於如何使用回播有實際上的建議，讓鳥友們可以一邊享受賞鳥的同時又能將回播對於鳥與其他鳥友的影響降到最低。
There is no debate that playback (playing a recording of a bird’s song) is one of the most useful tools in a birder’s struggle to see birds in the wild. Birds that might otherwise be too shy to come into the open can be lured into view by the sound of a potential rival. Whether this trickery has any significant impact on the birds is not so clear. Most of the debate has focused on the ethical question of whether or not playback should be used. In this post I assume that it will be used, and instead focus on suggesting some best practices to allow birders to enjoy the birds while minimizing the impact of playback, on birds and on other birders.
摘要
Summary
首先，重要的是在許多國家公園（或保護區）以及動物的庇護所中，使用回播鳥音是被完全禁止的。而干擾任何瀕臨絕種以及受威脅的物種也是違法的（回播絕對可以被解釋為是一種干擾的行為）（譯者註：此為美國現況）。因為在賞鳥活動熱門的區域裡，任何回播可能會對鳥施加任何潛在的不良壓力，所以在某些區域裡禁止回播的是一個很好的主意，而在其他地區，該在哪些情況下使用回播則是屬於各鳥友的自由心證。
First, it is important to point out that the use of playback is prohibited in many parks and refuges. It is also illegal to disturb any endangered or threatened species (and playback can be interpreted as disturbance). Any potential negative impacts of playback are more likely to occur in areas with a lot of birding pressure, so avoiding playback entirely in those places is a good idea. Where and how to use it in other situations is up the individual birder.
有效利用回播並減少對鳥的干擾
To be most effective and to minimize disturbance to the birds:
- 有計畫性的回播，選擇適當的地點以及了解回播的目標，不要只是播放鳥音。
- 片斷式的播放聲音－播放一次聲音不要超過30秒，保持安靜並暫停一陣子，播放五分鐘之後完全停止讓鳥休息，但仍然要保持警覺。
- 拿捏分寸是微妙的－你只是試著要引誘讓鳥出現在較明顯的區域，而不是引起一場鳥類間的戰爭。
- have a plan (choose your spot and know your quarry, don’t just play sounds)
- play snippets of sound – no more than 30 seconds at a time, then a long pause before the next snippet (more silence than playback) and after five minutes or so give it a rest (but stay alert).
- be subtle – you are trying to tease the bird into the open, not stir up a fight
降低對其他鳥友的干擾
To minimize disturbance to other birders:
- 不要造成其他鳥友的驚喜－宣布你即將要使用回播，並在播放回播時將設備置於肩膀之上，以免造成任其他鳥友的混亂或假警報。
- 保持較低的音量並使用間斷的聲音，避免非常大聲以及連續性的播放聲音。
- No surprises – Announce your intention to play a recording, and hold the device above your shoulder while it plays (to avoid any confusion or false alarms)
- Keep the volume low, and use only occasional snippets of sound. Do not broadcast loud or continuous sound.
回播的原理
How does it work?
回播的最佳時機是在繁殖季時使用在具領域性的鳥種身上，對雄鳥來說，聽到回播時會認為該聲音為入侵領域並威脅到自身繁殖的對手；理想上該領域的雄鳥會巡視領域，並鳴唱來對抗入侵者，或者會保持安靜並靠近其配偶，來降低雌鳥外遇的機率。對於雌鳥來說，有時候會接近回播以評估新來的雄鳥，或許可以得到配偶之外的關注。一般來說，使用回播在全年都可以引起鳥的注意，但對回播反應最強烈的情況是用在繁殖季且有領域性的鳥種，而無領域性如遷移中的鳥種反應就較為微弱。
Playback works best on territorial species during their nesting season, when the real bird thinks the recording is a rival threatening to encroach on either its territory or its mate. The territorial male will then (ideally) come out to confront the intruder by patrolling the edge of its territory and singing, or it may stay silent and close to its mate to guard against an adulterer. For her part, sometimes the female will approach the recording to assess the “new guy” and may even solicit some attention. Playback will arouse the curiosity of any species at any time of year, but the response is most dramatic from a territorial bird in breeding season, and weakest from non-territorial birds such as migrants.
回播的爭論
The debate
贊成回播的論述：
Arguments in favor of playback:
下列幾點是帶有推測性且/或主觀性的，假設你接受以自我為中心主義的前提之下，身為觀鳥者的我們一定需要看到鳥（這其實是另一個獨立的爭論我們一定需要看到鳥嗎？）：
These are speculative and/or subjective, and assume that you accept the self-centered premise that as birdwatchers we need to see birds (that is a separate debate):
- 回播使得鳥友們能更充分享受觀鳥的樂趣（在這方面來說與設置餵鳥點是類似的情形），回播可以吸引鳥類出現在較佳的觀賞位置。
- 回播可以減少入侵鳥類的棲息地的需要，因此（大概）可以減少對鳥類的干擾及棲地的破壞。例如在路邊回播能讓20個人看到鳥，會比讓20個人走進鳥的棲地裡理想。
- 回播可以吸引單一物種，而不打擾其他的物種，這或許比直接穿越過鳥的領域或使用混合性鳥音（編按：Pishing，混合多種鳥種的鳥音）來吸引廣泛的鳥種還要來得理想。
- 在某些情況之下回播鳥音可能會使雄鳥在其族群中增加牠的社會地位（請見下文回播的研究段落）。
- Playback allows people to enjoy birds more fully (in this way it is analogous to bird feeding). It attracts birds into view that would otherwise be difficult to see well.
- Playback reduces the need to physically invade the bird’s habitat, and therefore (presumably) reduces damage to the habitat and disturbance to the birds. For example, playing a recording from a roadside so that twenty people can see a bird is likely to be better for the bird than having those twenty people walking through the habitat.
- Playback targets a single species, without disturbing other species, which is presumably better than physically walking through a bird’s territory, or using broad-spectrum attractants like pishing, which affect all species.
- It’s possible that in some circumstances playback may increase the social standing of a male bird among its peers (see Research below)
反對回播的論述：
Arguments against playback
下列多數論點是帶有推論性的，只有第一項論述是在研究之中的記載，而最後兩項論述則是對其他鳥友「聆賞上」註1的影響：
Most of these arguments are speculative, only the first one listed is documented by research on one species, and the last two are aesthetic impacts on other birders:
- 積極性的回播（對該領域的鳥而言會被認為是失敗者）可能會導致雄鳥在競爭對手以及其配偶的面前失去其社會地位，使得雌鳥尋求配偶之外的雄鳥來交配（請見下文回播的研究段落）。
- 回播對鳥造成非自然性的壓力－領域中的雄鳥浪費能量去驅趕不存在的入侵對手。
- 回播引誘鳥出現在明顯的地方，增加被捕食的風險。
- 回播轉移鳥類的注意力，使牠們無法去做更有用的事情，例如覓食等。
- 鳥友不喜歡聽到電子化的鳥類聲音，因為有損他們體驗自然的觀鳥活動。
- 鳥友們會因為聽到回播而誤以為是該鳥種出現而造成混淆，並且知道是假警報後而有所失落。
- Aggressive playback (with the real bird coming away as the “loser”) can cause a male bird to lose status with rivals and its mate, leading the female to seek extra-pair copulations (see Research below)
- Playback causes unnatural stress on the bird – the territorial male wastes energy chasing a phantom intruder
- Playback lures birds into the open, exposing them to predators
- Birders dislike hearing an electronic recording, as it detracts from the “natural” experience of birding
- Birders experience increased stress from confusion and false alarms when the song of a sought-after species turns out to be a recording.
註1：aesthetic原本應該是美學的、審美的，用在這邊應該是指播放鳥音會破壞鳥友在觀察與聆聽的美感。所以建議用聆聽欣賞的「聆賞」去涵蓋原本的意思。
回播的研究
Research
沒有研究明顯指出回播對於鳥類有負面的影響，但這並不意味著這種做法是良好的，它只是意味著負面的影響從來沒有被紀錄到。而被紀錄到的影響有：回播增加了雄鳥體內的固酮濃度，以及增強了雌鳥的母性行為（如築巢等等）。
No research has demonstrated a negative impact of playback on birds. That doesn’t mean the practice is benign, it just means that no negative effects have ever been documented. Effects that have been documented include raised testosterone levels in males, and increased maternal behavior (nest-building, etc) in females exposed to playback.
一項研究發現了回播會影響雄鳥的社會地位：當在一隻鳥的領域中播放回播時，其鄰近的雄鳥及其配偶會觀察該雄鳥對於”入侵者”的反應。在Mennill等人(2002)的研究中發現，社會位階較高的黑頭山雀（Black-capped Chickadee）暴露在惡劣且長時間的回播之後失去了牠們的位階，因為其鄰居認為該雄鳥無法驅趕不存在的入侵者，這導致了雌鳥認為牠的配偶是不健全的，進而去尋求其他雄鳥來交配。研究同時指出這現象不會發生在位階較低的個體身上，但也可推測為如果鳥類暴露在適當的回播之下，會因為成功趕走不存在的入侵者而增加社會地位。
One study found an impact on the status of males. When song is played in a bird’s territory, that bird’s response to the “intruder” is watched attentively by neighboring males and by females. In one study (Mennill et al 2002) high-ranking male Black-capped Chickadees exposed to aggressive playback lost status as their mates and neighbors apparently perceived them as losers, unable to drive away the phantom intruder. This led to a loss of fitness as their mate went to other males to seek extra-pair copulations. That study found no change in the status of low-ranking males, but presumably birds exposed to infrequent playback could potentially gain status when they “win” the confrontation and drive away the intruder.
不過我必需要強調，上段僅是單一物種的研究，該研究結果如果非常典型，可能無法適用於其他物種。同時研究者普遍認為對於回播的影響了解甚少，但其影響可能（同時自相矛盾地）非常微小的。
It is important to stress that this is a single study, of a single species, and the results (if typical) may not be applicable to other species. Researchers generally agree that the effects of playback are poorly-known, but are probably (paradoxically) both far-reaching and small.
有證據指出鳥類很快就會習慣回播的鳥音，播放時間越長反應就越不明顯，最終完全忽略回播。有時候回播大聲的悲鳴聲被利用來防止鷗科或是椋鳥科在建築物上棲息；此外回播也能有效的吸引鳥類至適合的棲息地築巢繁殖，例如緬因州的海鸚鵡跟燕鷗及俄克拉荷馬州的黑頂綠鵙(Black-capped Vireo)。在這些例子中，回播代表適合繁殖的信號，而不會將鳥類趕出領域。
There is evidence that birds quickly become habituated to recordings, responding less strongly over time, and eventually ignoring the recordings entirely. Think of the loud distress calls sometimes played to keep birds like gulls or starlings from roosting on buildings. Additionally, playback has been used very effectively to attract birds to suitable nesting habitat (for example, puffins and terns in Maine , Black-capped Vireos in Oklahoma
甚麼事情不該做
What Not to do
在任何情況之下你都不應該持續或大聲的回播鳥音。回播典型的壞榜樣就是一邊走動一邊大聲播放連續性不間斷的鳥音，這種做法是無效且不必要的，是最有可能傷害鳥類以及干擾其他鳥友的行為。
Under no circumstances should you play a recording continuously or at very high volume. The epitome of bad playback etiquette is the birder who walks around with a device continuously and loudly broadcasting sound. This is ineffective, unnecessary, and is the kind of playback most likely to be harmful to birds and disturbing to other birders.
關於音量的小筆記：
我嘗試後發現iPhone 3G 內建的喇叭音量就足以用來回播吸引鳥類，儘管它並不是那麼的大聲但還是有用的，如果你使用有內建喇叭的機器，可以想想或許不需要外接喇叭，無論你使用什麼設備，剛開始回播的音量應該要略低於你想像中鳥類會有回應的音量。
A note on volume: I have found that the built-in speaker on the iPhone 3G is adequate for every playback situation I have tried, even though it is not as loud as an actual bird. If you are using a device with a built-in speaker, there is probably no need for an added, powered speaker. Whatever device you are using, your starting volume should be lower than the sound you imagine the bird would produce.
尊重所有鳥類
Respect for the birds
小心地計畫並了解你的目標，以便你猜測目標鳥種可能會出現的地點；如果你曾經聽過或是看過牠，將這些地點優先考慮做為回播的地點，你必需在或非常接近這些目標鳥種的領域裡回播才能獲得有用的反應。
Plan carefully and understand your quarry so that you can guess where the bird is, or where it is likely to be. If you have already heard it or seen it, consider those locations when deciding where to play audio. You must be in (or very near) the bird’s territory to get a useful response.
選擇觀察點－具體想像一下鳥可能會出現的情形：牠會如何出現在我們的視野中？如何接近回播的音源？可能在哪裡會讓你看到牠？你應該將回播設置在鳥類可能會感覺良好且願意接近的地點，該地點或許是在林間空地、植被外圍和/或有明顯的枝條的地方，讓鳥類可以清楚的被我們觀察。許多回播不成功的原因，或許是因為鳥類不願意穿越不適合的棲地，或是有茂密的植物讓鳥類隱密的接近音源。
Choose your spot and set the stage – Visualize the scenario of the bird coming into view. How will it approach the recording, and where will it sit so that you can see it? You should play the recording from a location that offers the bird a comfortable approach through its preferred habitat, and also has openings, edges, and/or prominent perches where it will come into view. Many playback efforts are unsuccessful either because the bird will not cross unsuitable habitat, or because dense vegetation allows it to approach closely while remaining hidden.
每次開始回播之前保持安靜幾秒鐘－例如回播二或三次的鳴唱然後停止，仔細看且仔細聽。
Begin by playing the recording quietly for just a few seconds – for example just two or three songs, then stop, watch, and listen.
使用短而片斷式的播放方法－當有回應時，試著使用短而片斷的播放方法，甚至一首完整的鳴唱聲只播放一半然後停止，這可以讓鳥被吸引出現，又不被認為該回播對於鳥類的領域或地位是個嚴重的挑戰。
Use short snippets – If there is any response, try very short snippets of song after that, even stopping the recording after half of a normal song, to try to tease the bird into the open without posing a serious challenge to its self-esteem.
注意任何回應－如果30-60秒之後沒有明顯的回應，再試著播放15-30秒的聲音。記住鳥可能會一邊保持安靜一邊接近，或者是守衛在牠的配偶身邊，沒有以聲音回應不代表沒有反應，而且你也應該假設你正被鳥觀察著；仔細觀察各處植物的騷動，看看是否有鳥類接近，同時也要小心觀察且聆聽鄰近領域雄鳥的反應。
Watch for a response – If there is no obvious response after 30-60 seconds, play another 15-30 seconds of sound. Remember that the bird may respond by approaching silently, or by guarding its mate, so a lack of song is not necessarily a lack of response, and you can assume that you are being watched. Watch the vegetation carefully on all sides for an approach, and also watch and listen for a response from neighboring males.
保持冷靜－如果你還是沒有發現任何回應，再次回播，觀察並等待，然後重複。但不要重複這些行為超過五分鐘，並且要避免使用完整且響亮的鳴唱聲來結束回播。
Remain calm – If you still don’t detect any response, play the recording again, watch and wait, and repeat. But don’t keep this up longer than about five minutes, and resist the urge to finish with a prolonged, loud barrage of song.
稍後一會再回來檢查－許多鳥在回播之後會保持安靜一陣子，直到幾分鐘之後才大聲鳴唱。鄰近領域的雄鳥也許會監視回播的情況，然後開始挑戰鄰居，在數分鐘之後也受到刺激開始鳴唱。如果你可以在附近等待或者在10到30分鐘之後回來查看，你或許可以發現預期的回播反應。
Check back later – Many birds will remain silent in the immediate aftermath of the playback, and then begin singing vigorously minutes later. Males in other territories might monitor the playback, and the challenge to their neighbor, and also be stimulated to sing minutes later. If you can wait around, or circle back to check on the area after 10 to 30 minutes, you may find that the desired response to playback is occurring then.
尊重其他鳥友
Respect for fellow birders
禮讓－在開始回播之前請禮貌的詢問附近的鳥友是否有人反對回播鳥音。
Be courteous – Before starting, ask your fellow birders if anyone objects to using playback.
不要嚇到其他鳥友－在每次回播之前可以小聲的告知其他人自己將要播放鳥音了，並在播放的過程中將設備高舉過頭，讓其他鳥友知道音源的來處。
Don’t surprise people – Before each burst of playback, announce to the group that you are about to start playback (just quietly saying “playback” will do), and hold the device up above your head during playback so other birders can see at a glance the source of the sound.
不要太顯眼－壓低回播的音量且短暫僅播放片段的聲音－30秒或是更少－然後停下來觀察並且聆聽其反應。
Be unobtrusive – Keep the volume low and play only short clips of sound – 30 seconds or less – then pause to watch and listen for a response.
結論
In conclusion
利用回播就像是釣魚試圖讓魚咬誘餌一樣，你可以有效的吸引一隻鳥進到容易觀察的區域。如果一條魚忽略了你的誘餌，那麼你並不會換一個更大更好的誘餌並丟在魚的上方。是的，你會使用一樣的誘餌，小心且輕柔地放在魚的後方，並隨時變換自己的技巧讓魚上鉤。同樣地，如果你正在想辦法吸引鳥到較明顯的區域並對你好奇，你的下一個動作應該要重複但放輕動作，增加技巧性，試著激起鳥類的好奇心。
With playback, you are effectively teasing a bird into the open, just like trying to get a fish to bite a lure. If a fish makes a pass at your lure on one cast, you wouldn’t switch to a bigger, more colorful lure and throw it right on top of the fish. No… you would use the same lure, cast it carefully and gently beyond the fish, and retrieve it with as much finesse as you can muster. In the same way, if you are trying to attract a bird into the open and it shows some interest in what you are doing, your next move should be the same thing again but lighter, with more finesse, trying to pique the bird’s curiosity.
正如其它所有跟鳥類相關的事物一樣，我們對於鳥類與回播之間的影響還有許多不清楚的地方。我們需要研究不同社會結構下不同鳥種對於回播的反應，這會對我們使用回播這項工具更有幫助。在尚未清楚瞭解回播對鳥產生何種影響的同時，我們應該要保持禮貌與尊重對待鳥類以及其他的鳥友，避免產生衝突，讓我們在對鳥類產生最小的影響之下一起愉快的賞鳥。
As in all things related to birds, there is a lot that is unknown about their response to playback. More research on the effects of playback, including varied species with different social systems, would be very helpful. In the meantime, being courteous and respectful to the birds and to fellow birders should avoid most of the potential conflicts and allow us to continue to enjoy birding with minimal impact on the birds.
參考文獻
References
Mennill, D. J., L. M. Ratcliffe, and P. T. Boag. 2002. Female Eavesdropping on Male Song Contests in Songbirds. Science: 296: 873 http://web2.uwindsor.ca/courses/biology/dmennill/pubs/2002Science873.pdf
Sen, S. K. Bird Call Playback, Ethics and Science. Web page accessed 7 Apr 2011. http://www.kolkatabirds.com/callplayback.htm
