The Italian pressure worked. The French had always intended to restore the destroyers to Brindisi as soon as possible and had planned to free some by reorganizing the supply services to Salonika. On 10 December Admiral Lacaze, the minister of marine, directly ordered the French commander in chief to send enough destroyers to Brindisi to bring the number up to the requisite six, so that the Italians would resume supplies. Abruzzi promised to recommence sending supplies to Valona, where unloading was easier, but would only promise to “try” to resume landing food and matériel at Durazzo and San Giovanni, where the unprotected harbors lacked facilities for unloading and were now partially blocked by sunken ships.29
The situation had deteriorated beyond the point where any infusion of supplies could be of use. The chaotic conditions in northern Albania, the slow advance of the Austrian army, the disorganized condition of the Serbian army harassed by Albanian tribesmen as it retreated, and the flood of civilian refugees all pointed toward evacuation as the only feasible solution. But could they evacuate? The Austrian army was for the moment less of a threat as logistical difficulties had slowed its advance. Evacuation from San Giovanni was very difficult, however, because the troops had to be ferried out to ships offshore and progress was painfully slow. Austrian air raids added to the misery. The Allies therefore tried to get as many of the Serbians as possible farther south to Durazzo or Valona. On 5 December the Italian high command ordered a brigade of Italian troops northward from Valona to secure Durazzo. The winter rains turned what passed for roads into quagmires, and the Italian troops did not reach Durazzo until the 19th.
What of the Austrian navy? Would or could it make any attempt to interfere with the evacuations? On 28 December Haus cabled the rear admiral commanding the Austrian naval forces at Cattaro that aerial reconnaissance and other intelligence revealed that two Italian destroyers had brought approximately 300 troops to Durazzo. He ordered the Austrian cruiser flotilla to attack them. As a result, Linienschiffskapitän Seitz was given oral instructions to sail with the Helgoland and five Tátra-class destroyers to search the waters between Brindisi and Durazzo for the two destroyers. If Seitz did not encounter them, he was to proceed to Durazzo by dawn and sink any destroyers or cargo ships found there. This Austrian attempt to pick off isolated forces led to the action on 29 December, the most significant so far of the war in the Adriatic.
The Austrians failed to encounter any Italian destroyers either at sea or in Durazzo, but they surprised the French submarine Monge on their way south, and the submarine was sunk by the destroyer Balaton. At daybreak four of the Austrian destroyers entered the harbor of Durazzo and sank a Greek steamer (with Italian crew) and a large and small schooner. Shore batteries opened fire on the Austrian destroyers as they were leaving, and they turned sharply to port, supposedly to avoid masking Helgoland’s line of fire. The maneuver brought two of them into a minefield; the Lika was sunk and the Triglav badly damaged. The situation now became serious for the Austrians. They lost approximately one and three-quarters of an hour picking up survivors of the Lika and trying to get the Triglav under tow. The first attempt by the destroyer Csepel failed when the tow fouled her screw, greatly reducing her speed. The Tátra did manage to get the Triglav under tow, but the Austrians could not make more than 6 knots.
Would the Allied forces at Brindisi be able to intercept? The Italian commander in chief at Brindisi, Vice Admiral Cutinelli-Rendina, received the alarm shortly after 7:00 A.M. and ordered the British and Italian light cruisers Dartmouth and Quarto to sail immediately. Five French destroyers were to follow as soon as they had steam up. Rear Admiral Bellini, the commander of the Italian Scouting Division, flying his flag in the Quarto, was senior Allied officer afloat during the action. The Weymouth, the other British light cruiser at Brindisi, was ordered to raise steam but not sail until Cutinelli had further intelligence of Austrian movements. Her captain, Denis Crampton, chafing at his inaction, pleaded with Cutinelli: “For God’s sake let me go out.” The Weymouth was finally ordered to sail at 9:00 A.M. and left with the Italian light cruiser Nino Bixio and four Italian destroyers.
Seitz was now in a dangerous position, for by midmorning there were four British and Italian cruisers (armed with 6-inch and 4.9-inch guns) and nine French and Italian destroyers trying to cut off the Helgoland (armed with 3.9-inch guns) and three destroyers (one with damaged screw) towing the crippled Triglav. Seitz sent a wireless message for help, and the Austrian commander at Cattaro sent out the armored cruiser Kaiser Karl VI and four torpedo boats in support. The armored cruiser, with two 9.2-inch guns, but relatively slow at 20 knots, was actually more powerful than any of the Allied ships, but although she came close enough to see smoke from the Allied ships in the distance, she did not take part in the action. The old battleship Budapest, the small cruiser Aspern, and the light cruiser Novara, raised steam and sailed later in the day but were never near the action. Neither were the three Regina Elena-class fast light battleships (two 12-inch guns, 20 knots) at Brindisi. Cutinelli did not order them to sea, again demonstrating the Italian reluctance to risk capital ships in the Adriatic.
With the Allied forces between his force and safety at Cattaro, Seitz had no choice but to abandon the Triglav. He hoped that the Austrian submarine U.15, on patrol in the vicinity, would attack any Allied ship that came upon the destroyer, which the Austrians attempted to scuttle. U.15 was not, however, in position to make an attack when the five French destroyers arrived and finished off the wreck. The French commander in chief later criticized them for wasting too much time on the wreck, for they could not catch up with the cruisers and saw no further action that day.
The afternoon of 29 December saw a high-speed chase with most of the gunnery exchanges taking place at extreme range and with the Helgoland frequently outranged. The Austrians had the advantage of speed, even though the Allies were between them and safety. Seitz steamed westward and south westward almost up to the Italian coast, all the while trying to work around his pursuers. Darkness permitted him to make his escape. Thursby thought that half an hour’s more daylight “would have done it” and blamed Bellini for poor handling of the Allied forces. There was general dissatisfaction that the Austrians, with a much smaller force, had gotten away. There was also dissatisfaction on the Austrian side. Seitz may have been praised for his cool handling of the Austrian force in a difficult position, and the Austrian ships may have received hearty cheers from the other Austrian warships at Cattaro on their return, but Seitz was raked over the coals by Haus. Instead of the anticipated praise, he was greeted with the words, “Herr Captain, you thus ran away, you ran away very ably.” Haus considered the failure of the Lika and Triglav to follow in the wake of their leader in waters suspected of containing mines an inexcusable error leading to the loss of the two destroyers and bringing the entire flotilla into the greatest danger. Haus also termed the fouling of the Csepel’s screw in attempting to tow the Triglav “ineptitude” and “carelessness.” He faulted Seitz for apparent tardiness in sending wireless reports to Cattaro, which resulted in delay in the sailing of the relief force, and for omitting to adequately inform Cattaro of the location of the destroyers; and he criticized Seitz for his failure to plan or execute a torpedo attack with the three surviving destroyers on the two nearest pursuing cruisers after nightfall. Haus relieved Seitz of his command, a move that some Austrian naval officers believed was unjust. Haus’s reaction on close examination is understandable. The Austrians had accounted for a French submarine, a steamer, and two schooners, but had lost two of their best destroyers and only just saved a flotilla with one of their most modern cruisers and three of their best destroyers. For a commander whose policy was based on the fleet-in-being, it was an unacceptable exchange.30
The offensive by the Central Powers in the Balkans paid the Austrian navy a major dividend. On 8–10 January 1916, the XIX Austrian Army Corps, effectively supported by naval gunfire from the old battleships and cruisers of the Fifth Division, cleared the Mont
enegrins from Mount Lovčen. This removed observation posts that could report all Austrian ship movements during daylight hours. The Montenegrins requested an armistice on 12 January and dropped out of the war.
The evacuation of the Serbian army and civilian refugees through San Giovanni came to an end by 22 January, and the center of activity shifted southward to Durazzo. The evacuations here ended by 9 February, but the Italians delayed evacuating the port. This was a mistake if they did not intend to hold on to the place. When the Italian army finally left, during the nights of 25–27 February, they were forced to do so under fire and suffered more than 800 casualties. The remaining evacuations took place through Valona. The French sent two large armored cruisers to help cover them, and the British drifters that had arrived at the Strait of Otranto in the autumn of 1915 also did notable work covering the movement between Valona and Corfu. The majority of the steamers and covering forces were Italian. The Italians lost six, and the French two, steamers during the evacuation. Thursby, the commander of the British Adriatic Squadron, praised the duke of the Abruzzi when he wrote the First Sea Lord on 20 February:
We have moved altogether in the last two months over 200,000 people including Servians [sic], Austrian prisoners & Italian troops with hardly a casualty. I do not think that with the scratch pack we have had to deal with, ships & material being supplied by 3 different nations, anyone but the Duke could have done it. In addition to being able & energetic, his position enables him to do more than any ordinary Admiral could do. From a naval point of view it has been a much more difficult operation than the evacuation of Gallipoli.31
The national rivalries among Italians, French, and, later, Yugoslavs colored accounts of the event, and to a certain extent they still do. By April 1916 more than 260,000 Serbian military and civilian refugees and Austrian prisoners of war had been evacuated. The remnants of the Serbian army—roughly 160,000 men—were brought to Corfu, rested, reorganized and reequipped, and eventually brought to Salonika to serve on the Macedonian front. The rescue of the Serbian army from certain destruction, whether by starvation or capture, and their resurrection to fight another day was one of the more notable achievements of sea power in the First World War.32
The Austrian navy missed a big opportunity to inflict major damage by failing to seriously interfere with the evacuation. On 27 January, responding to the reports from aerial reconnaissance that there were eight steamers and five destroyers at Durazzo, the light cruiser Novara and two Tátra-class destroyers sailed to raid the port. The two destroyers were damaged in collision with each other and had to turn back. The Novara continued alone, only to meet the Italian cruiser Puglia and French destroyer Bouclier. There was now no possibility of surprise, and the Novara broke off the action and returned home. On 6 February the Helgoland and six torpedo boats set out to raid the transport route between Durazzo and Brindisi but encountered the Weymouth and Bouclier, and in the action that followed, two of the Austrian torpedo boats collided with each other, damaging one badly enough to force it to return to base. Once again the possibility of surprise was lost and the Austrians broke off the action. On the same day, the British light cruiser Liverpool and the Italian destroyer Bronzetti chased the Austrian destroyer Wildfang, which had been on reconnaissance, back to Cattaro. Heavy weather frustrated Austrian operations on the 23d and 24th of February, and on the 26th the Helgoland and six destroyers failed to find any enemy craft off Durazzo.
In summary, during the months of January and February 1916, bad weather or action by Allied screening forces, which destroyed the essential element of surprise and put the Austrians in danger of being cut off by superior forces, thwarted action by the light forces of the k.u.k. Kriegsmarine against the evacuation. What of the Austrian heavier units? Did Haus miss the opportunity to inflict serious losses on the Allies? Haus was apparently convinced there were too many large Allied ships in the southern Adriatic capable of intervening and overwhelming his forces. The trend in Austrian historiography has been to become more critical of Haus and his policy of maintaining the fleet-in-being. It would have been wrong to take foolish risks, but there were times when certain risks were justified and, if taken, might have resulted in great achievements. On the other hand, there was a sizable number of Allied submarines in the Adriatic and there were very real dangers. The Allied submarines had not achieved much, partially through lack of suitable targets, although a French submarine had sunk an Austrian transport off Cape Planka on 28 December. The results that might have followed the use of Austrian capital ships against the Serbian evacuation is another of those arguments that can never be settled. AOK and the Austrian army also could be faulted for not trying to push farther south in Albania and capture Valona. With Valona in Austrian hands, the Allies might have had a much more difficult time trying to maintain the blockade of the Strait of Otranto.33
After the evacuation of the Serbian army, the war in the Adriatic became even more one in which naval guerrilla war flourished. The Italians developed ingenious new weapons, and the Allies in the Adriatic and the Mediterranean as a whole became more and more concerned with the submarine war. The Germans increased their submarine flotillas at Pola and Cattaro, and they achieved spectacular success in the Mediterranean. The unfortunate friction between the French and Italians remained, and so too did the threat from the Austrian fleet-in-being.
THE DRIFTER PATROL AND THE OTRANTO BARRAGE
The first of the British drifters arrived in September of 1915. The British had offered drifters and trawlers with antisubmarine nets for the Strait of Otranto at the moment Italy entered the war, but initially the Italians were not interested. They changed their minds, and with German submarines regularly passing through the Strait during the summer, the Admiralty was glad to send them. By the end of September, sixty had arrived, at first without organization or stores. Thursby sent two divisions out to lay nets in the Strait as soon as possible. An Italian merchant ship acted as depot at Brindisi. Thursby hoped to establish a pattern of two divisions out and one in port, with thirty-five to forty drifters out at a time. Thursby managed to arm most of his drifters, but he quickly discovered he did not have enough drifters: “It is a big place to watch and we want more depth to our screen.” The impending winter weather in the Adriatic meant rough seas in which nets would be lost and boats frequently would have to take shelter from the characteristic short, steep seas. Thursby revised his estimate upward; they would need forty boats out at a time, and with the necessary docking and repairs they would need eighty boats on station. Thursby, after a tour of inspection in a destroyer, realized what a small chance of catching a submarine there was with so few drifters. The Admiralty decided in mid–November to send another forty, which began to arrive the following month.34
There is something almost quaint about the idea the little drifters would be able to “catch” a submarine in their nets, that is, cause the boat to foul its screw or betray its presence or force it to the surface so that one of the destroyers on the Otranto patrol might move in to finish it off. Thursby and other British commanders were optimistic that they had accounted for submarines, but owing to the inherent nature of submarine warfare, they could not confirm the “kill.” The drifter patrol actually had little success in stopping submarines. In 1916 most submarines ran through the blockade on the surface at night. The experience of submarine commanders varied; some might be forced to submerge by the presence of drifters or a destroyer but they would still get through. It is also somewhat misleading to talk of a “barrage,” or even of a “line” of drifters. This would suggest a continuous line of small ships with nets constituting a serious barrier to submarines. The real Otranto barrage was far different. A French officer, one day in July 1916, found on a tour of inspection in a destroyer that only 37 of what should have been a daily average of 50 drifters were out, and that only 10 actually had their nets in the seas and the Adriatic currents had caused the groups to drift far apart. Thursby’s successor, Rear Admiral Mark Kerr, reporte
d that the Adriatic currents were not only strong, they were unpredictable. Even if the drifter line had been accurately placed the evening before, on most days they would drift 10 miles apart during the night. Kerr thought they really needed drifters deployed in two or three lines with intervals between them of 10 to 15 miles. They also needed far more drifters—say, 300—to make a truly effective barrage. The drifters actually caught only one submarine, the Austrian U.6, on 13 May 1916. Two other submarines, the German UB.44 in August 1916 and the Austrian U.30 in April 1917, disappeared without a trace, and one or both might have been lost in the barrage, perhaps to a mine.35
By April 1916 the British drifters had extended their patrol area to a distance of 80 miles from Brindisi and 40 miles wide at its narrowest point. The strain of constant work with the number of drifters available began to tell, and in April 1916 Thursby applied for an additional 40 drifters. The Admiralty, after much discussion, could not pry more than 10 out of Jellicoe, for by now the little craft were badly needed for the antisubmarine campaign in home waters. The Admiralty managed to send approximately 20 more in the closing months of 1916.
With the detachment of drifters and destroyers for other duties, such as convoying the reorganized Serbian army from Corfu to Salonika in May 1916, even an early enthusiast such as Thursby had to admit that the Otranto patrol was practically nonexistent. The elusive goal remained, however, with the idea that if one could just get enough drifters and make the patrol cover enough depth, submarines might be compelled to travel submerged long enough to exhaust their batteries. The Otranto barrage was later strengthened through the introduction of a fixed net fitted with mines, and by 1918 the Otranto barrage was more elaborate, with plans to make it even stronger after the Americans entered the war and arrived in the Mediterranean. The system claimed another German submarine in the summer of 1918, largely because its commander did not realize the obstructions had been extended and take the requisite measures to avoid them. But the results of the different Otranto barrages were never in the least commensurate with the efforts expended on them.36
A Naval History of World War I Page 28